JP2000233502A - Ink-jet recording head and ink-jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet recording apparatus capable of preventing ink adhesion onto a recording electrode tip end and capable of obtaining a highly fine image without displacement of the ink ground position. SOLUTION: An ink-jet recording head comprising a heat substrate 10, an ejecting member 12 disposed thereon, a recording electrode 11 disposed interposing the ejecting member 12, for ejecting an ink from the ejecting member, and a partition wall 13 for enveloping the recording electrode 11, wherein the ink is supplied from the base end of the ejecting member 12 so as to be collected upward from the vicinity of the tip end of the ejecting member 12, is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for printing an image by depositing ink droplets discharged from electrodes of a recording head on a recording medium, and more particularly to the structure of an ink jet recording head.

[0002]

2. Description of the Related Art An ink jet recording apparatus that prints an image by ejecting a small amount of ink droplets from a minute ejection portion and depositing the ink droplets on a recording medium guides the ink from an ink tank to each ejection portion, and the ink is printed. By applying kinetic energy to the recording medium, the ink droplets are ejected from the ejection section and adhere to the recording medium to form dots. As one of driving methods for applying kinetic energy to ink, there is a method (electrostatic recording method) in which a voltage is applied between a recording electrode and a common electrode in contact with a recording medium, and the ink is ejected by electrostatic force. In this method, since the amount of ink ejected on a recording medium can be controlled by pulse width modulation of a voltage applied to a recording electrode, the method has been attracting attention as a method for realizing a high-definition inkjet printer.

As an example of such a system, Japanese Patent Application Laid-Open No. 7-502 is disclosed.
In No. 218, an ink in which a coloring agent was dispersed at a low concentration in a solvent was supplied to the recording electrode surface, and a voltage was applied to the recording electrode to form an electric field, and the charged coloring agent was aggregated and concentrated. A method of discharging ink from a recording electrode onto a recording medium is described.

Further, in WO97 / 27058, ink is flowed in a square-shaped channel having a rectangular cross section, and the square-shaped corner is arranged so as to be closest to the recording medium, and is provided in the channel. A technique is described in which a voltage is applied to a linear electrode to cause ink to fly from the position of a square corner.

[0005]

In the electrostatic recording system disclosed in the above-mentioned publication, ink is circulated, a bias voltage is applied to a recording electrode, and the ink in which the pigment component is concentrated is supplied to the tip of the recording electrode. In this state, a pulse voltage is superimposed and applied to a recording electrode in that state, thereby discharging concentrated ink toward a recording medium to record an image. Further, in this method, since there are no small holes in the ink ejection section, clogging of the ink hardly occurs. Therefore, even if the recording head is formed in a line shape, a defective portion where ink is not ejected hardly occurs, so that an ink jet recording apparatus having a line head can be easily realized. A recording apparatus having a line head has a feature that high-speed printing is possible because recording can be performed simultaneously on the entire width direction of the recording medium.

In this method, concentrated ink is ejected by applying a voltage obtained by superimposing a pulse voltage on a bias voltage to a recording electrode. However, when the pulse voltage is applied, all of the concentrated ink is not ejected. In addition, when the discharge is repeated in which a very small amount of concentrated ink remains at the leading end of the recording electrode, a problem that the ink gradually adheres to the leading end of the electrode tends to occur. If the ink sticks to the tip of the recording electrode, the point at which the electric field is concentrated shifts, so that the flying direction of the ink shifts, and the image on the recording medium is disturbed.

[0007] JP-T-Hei 7-502218 and WO 97/2705
In Japanese Patent Application Laid-Open Publication No. 8 (1999) -1999, there is no consideration that the ink sticks to the electrode tip, so that a problem that the flying direction of the ink is shifted at the time of recording and the image is disturbed easily occurs.

Further, in the present recording system, if there is no member for partitioning the ink between the electrodes arranged in a line, the potential applied to the recording electrode is transmitted to the adjacent recording electrode through the ink. Therefore, the intensity distribution of the electric field around the electrode A changes depending on the presence or absence of ink ejection at an electrode adjacent to one electrode (electrode A) for ejecting ink, so that the direction of ink ejection from the electrode A is shifted. However, there is a problem that an image is disturbed as in the case of ink fixation.

However, in a recording head having a narrow electrode gap even if a member for separating ink is provided, the electric field distribution around the electrode A depends on whether recording is performed simultaneously on a channel adjacent to the channel where the electrode A for recording exists. Changes. If the electrode spacing is widened so that this change in the electric field distribution does not occur, the number of dots per unit area decreases, and a new problem that a high-definition image cannot be obtained arises.

In the example of JP-A-7-502218, since there is no partition between the electrodes arranged in a line, a pulse voltage is applied to the recording electrode of the channel adjacent to the electrode A of the recording channel. The intensity distribution of the electric field around the electrode A changes depending on whether or not the printing is performed, and the flying direction of the ink is shifted, so that the image is easily disturbed. In the embodiment of WO97 / 27058, there is a member for partitioning the ink. However, since there is no point where the electric field is concentrated in each channel, the ink discharge point is not fixed at one point, and the ink discharge point is not fixed. In this configuration, the flight direction becomes unstable.

The present invention has been devised to solve the above-mentioned problems based on the principle of ink ejection in this recording method.

That is, an object of the present invention is to provide an ink jet recording apparatus which can prevent ink from sticking to the leading end of a recording electrode, and can obtain a high-definition image without a displacement of an ink landing position due to a displacement of a discharge point. .

[0013]

According to the present invention, in order to achieve the above object, an ink jet recording apparatus has the following configuration.

A substrate, a discharge member disposed on the substrate, a recording electrode disposed to sandwich the discharge member, for discharging ink from the discharge portion, and a covering portion including the recording electrode. And the ink is supplied from the base of the ejection member, and is collected upward from near the tip of the ejection member.

[0015] With the configuration in which the covering member surrounds the ejection member, the ink flow path can be individualized, and the potential applied to the recording electrode for ejecting ink is applied to the surrounding recording electrode or ejection member through the ink. The transmission of the ink is prevented, the electric field distribution at the recording electrode of the channel for discharging the ink is stabilized, and the ink discharging method is stabilized. In addition, by using a flow path configuration that has a component that causes ink to flow from the base of the ejection member toward the tip toward the individualized ink flow path and returns to the base direction just before the flight point, the ink can be discharged at the time of ink discharge. The ink concentrate that has not been ejected toward the recording medium can be collected from the tip of the ejection member, thereby preventing the ink from sticking at the tip of the ejection member.

Further, it is possible to provide an ink jet recording apparatus in which the recording heads are arranged in multiple stages so that the ejection members are arranged in a staggered manner, and high-speed, high-definition recording is possible.

[0017]

FIG. 4 shows an embodiment of an ink jet recording apparatus according to the present invention. 1 is a housing, 2 is a recording head, 3 is a refill ink tank, 4 is an ink circulation system, 5 is an ink ejection section, 6 is a common electrode, 7 is a recording medium, 8 is a recording medium transport path, and 9 is a recording medium. It is a transport device.

In the housing 1 of the ink jet recording apparatus, a recording head 2 for discharging ink and an ink discharging section 5 are provided.
A common electrode 6 provided at a position opposed to the common electrode 6, a recording medium transport device 9 for passing the recording medium 7 between the ink discharge unit 5 and the common electrode 6, and a controller for controlling the entire device are built in.

The recording head 2 includes an ink tank 3, an ink circulation system 4, and a large number of ink ejection units 5 arranged at appropriate intervals in a part of the ink circulation system 4.
Are arranged so as to intersect the direction in which the recording medium 7 is conveyed. In an ink jet recording apparatus capable of performing color printing, the recording heads 2 are arranged at least for each of the colors cyan, magenta, yellow, and black.

The recording medium transport device 9 is a motor (not shown).
And transports the recording medium 7 on the recording medium transport path 8. Normally, a bias voltage of about 1.5 to 2 kV is applied to individual recording electrodes present in the ink ejection section 5 of the recording head 2, and a pulse voltage of about 0.5 kV is applied in accordance with a recording signal. By applying the bias voltage, the colorant components in the ink circulated in the ink circulation system 4 are collected at the tip of the ink ejection unit 5. Then, when a pulse voltage is applied, ink is ejected from the tip of the ink ejection unit 5. The ink that is reduced by discharging is supplied from the ink tank 3. As the ink to be used, for example, an ink in which a charged pigment is dispersed together with a charge control agent in a petroleum-based solvent such as isoparaffin having a low viscosity of about 1 to 10 mPa · s can be used. The ink circulation method and the configuration of the ink discharge unit 5 will be described later in detail.

First, the ink circulation system 4 will be described.

FIG. 5 is a diagram showing the configuration of the ink circulation system. The ink circulation system 4 includes an ink reservoir 21, an ink flow rate adjustment chamber 24, a pump 22a controlled by a controller,
22b and piping 23, 25, 26, 27. As shown in FIG. 6 as an example, an ink level detector 32 for detecting the ink level is attached inside the ink flow rate adjustment chamber 24, and the detected value is used to control the pump 22a. Feedback will be given. The ink circulation system 4 configured by these components is divided into an ink supply system for supplying ink to the ink ejection unit 5 and an ink collection system for collecting ink from the ink ejection unit 5. In the ink supply system, the ink pool 21
Is sucked up by the pump 22 a and sent to the ink flow rate adjustment chamber 24. Further, since the pump 22 a is driven so that the deviation between the detection value of the ink liquid level detector 32 and the target value is reduced, a predetermined amount of ink exists in the ink flow rate adjustment chamber 24.

The ink that has entered the ink flow control chamber 24 is:
Since the liquid flows toward the ink discharge unit 5 where the discharge electrodes are arranged at a pressure based on the potential energy determined by the liquid level difference between the ink flow control chamber 24 and the ink discharge unit 5, a constant pressure and flow rate can always be obtained.

Further, the ink recovery system uses the pump 22b to collect the ink that has passed through the ink discharge section 5 into the ink pool 2.
Collect in 1.

Printing is performed after these ink circulations have stabilized.

The ink circulation system 4 shown here is merely an example, and any other method may be used as long as it supplies and recovers an appropriate amount of ink to the ink ejection section.

Next, the configuration of the ink discharge section 5 will be described.

FIG. 2 is a configuration diagram around the ink ejection section 5 of the ink jet recording apparatus used in the present invention. On the head substrate 10 made of an insulating material having a low dielectric constant such as glass,
There are ejection members 12b and 12c having a convex portion at the tip, and a partition wall 13 provided to partition the ejection members 12b and 12c to form an ink chamber. The part that becomes the ink chamber is U-shaped, and the U-shaped part is
For example, the recording electrode 11b is present so as to surround the ejection member 12b. The ink is supplied to a region surrounded by the partition 13,
When a pulse voltage is applied to the recording electrode 11b in accordance with the image signal, the ink in which the pigment components are collected is discharged from the ejection member 12b.
Is ejected toward the recording medium 7 from the front end of the recording medium. This phenomenon is
The potential applied to the recording electrode 11 is transmitted through the insulating ink, the potential of the ejection member 12 is also substantially equal to that of the recording electrode 11, and the electric field at the tip of the ejection member 12 closest to the recording medium becomes strongest. This causes ink to be ejected toward the recording medium. If the height of the partition 13 is higher than the height of the ejection member 12, the ink easily flows in the individualized ink flow path.

The recording electrode 11 may be disposed at a position in contact with the ink or inside the partition 13. However, depending on the ink used, if the recording electrode 11 is in contact with the ink, the recording electrode 11 In some cases, ink adheres to the surface. In such a case, the recording electrode 11 is installed inside the partition wall 13 so as not to come into contact with the ink to prevent the ink from sticking to the surface of the recording electrode 11.

Of the supplied ink, the ink that has not been discharged toward the recording medium 7 is recovered from the discharge position by a recovery unit (pump). This will be described with reference to FIG.

FIG. 1 is a sectional view taken along a dotted line aa 'in FIG. (Note that FIG. 2 is a cross-sectional view taken along the dotted line bb 'in FIG. 1.) In this embodiment, as indicated by the arrow, an appropriate amount of ink supplied from the ink supply unit is supplied to the ejection member. 1
2 flows from the root to the tip, is collected so that the traveling direction is reversed near the tip, and the ink circulates through the individualized region because the ejection member is sandwiched between the partition walls 13. . By adopting such an ink circulation configuration, the ink can be circulated stably, and stable ejection of the ink becomes possible. In addition, a part of the partition 13 is 50 to
It protrudes 250 μm. If the protrusion length is shorter than 50 μm, an ejection point may be formed on the head substrate 10, resulting in improper ink ejection. Also, the protrusion length is 25
If the thickness is 0 μm or more, there is a problem that the circulating ink leaks from the head substrate and contaminates the inside of the recording apparatus. In addition, the discharge member 12 is 20 to 100 more than the partition 13.
Protrude by μm. Beyond this range, the reproducibility of the size of the ejected dots deteriorates. This cause will be described with reference to FIG.

FIG. 12 shows the discharge member 1 during ink circulation.
2 shows an ink curve shape (hereinafter, referred to as an ink meniscus) formed between the ink jet head 2 and the tip of the partition wall 13. The ink meniscus 18 is formed by the surface tension of the ink, and serves to guide the ink to the tip of the ejection member 12. FIG. 12A shows the discharge electrode 12.
Represents the ink meniscus when a bias voltage is applied to the ink. When a bias voltage is applied, an electrostatic force is applied to the pigment component in the ink, so that the pigment components gather toward the tip of the ejection member 12. When a pulse voltage corresponding to the image signal is applied thereto, the electrostatic force acts more strongly and the ejection member 1
The pigment in the ink moves to the leading end with the ink solvent, and is discharged toward the recording medium. FIG. 12 (b)
It shows an ink meniscus at the time of ink ejection. If the step between the ejection member 12 and the partition 13 is 20 μm or less, the amount of ink going to the tip of the ejection member 12 is too large, so that the ink ejection amount at the time of pulse application may become excessive, and the image quality becomes unstable. . On the other hand, if the step exceeds 100 μm, it becomes difficult to supply ink to the tip of the ejection member 12, the ink ejection amount becomes too small, and the image becomes unstable.

Here, the movement of the pigment in the ink at the tip of the ejection member 12 during printing will be described. After ink is ejected by superimposing and applying a pulse voltage to the bias voltage based on image information, the ink meniscus is shown in FIG.
Then, the state returns to the state of FIG. When the ink returns in the direction of the root of the ejection member 12, the pigment concentrate remaining on the tip of the ejection member 12 by the circulation of the ink is collected. This is achieved by reversing the ink circulation direction at a slightly root side of the tip of the ejection member 12 and collecting the ink.
2 generates a force for drawing the dark ink into the circulating portion from the front end of the discharge member 2 to prevent the adhered matter from adhering to the front end of the discharge member 12. If a fixed substance is generated at the tip of the discharge member 12, one end of the fixed substance serves as a discharge point, which causes a problem that the ink discharge direction is changed and the image is disturbed. Since no fixed matter is generated at the tip of the member 12, the ink is ejected in a predetermined direction and the image is not disturbed.

As described above, the partition 13 and the discharge member 12
The electric field is concentrated at the tip of the ejection member 12 and the ink is supplied and collected so that only a required amount of ink is present at the ejection point, so that the ink is ejected with a small electrostatic force. be able to.

The recording head of the present invention performs recording while circulating ink. However, since the ink is collected using a pump, the protrusion amount of the partition wall and the ejection member falls within the above range. If set, the ink ejection direction can be any direction from a vertical direction to a direction directly below.

Next, a method for increasing the above effect by increasing the ink collecting power will be described with reference to FIG.

FIG. 3 is a sectional view taken along the line cc 'in FIG. Above the ejection member 12 and the partition 13, a thin insulating layer 14 having an ink inlet 17 and a V-shaped cut 15 is provided.
Exists. The ink enters the flow path surrounded by the partition 13 from the ink inlet 17, and flows along the ejection member 12 with the insulating layer 14 acting as a lid. The ink is collected from the V-shaped cut 15 located immediately above the vicinity of the tip of the ejection member 12, and the ink flow speed is increased particularly in a narrow cut width, so that the ink is collected strongly.

FIG. 11 is a diagram of the recording head as viewed from the recording medium 7 side, and shows the flow of ink near the ink ejection section.

Next, an example of a method for manufacturing the recording head will be described.

First, a groove is formed in a head substrate 10 made of glass or the like having a thickness of about 1 mm using a dicing saw. The groove has a width of about 0.2 to 0.5 mm and a depth of about 0.2 mm, and is present in the direction in which the ejection members serving as flying parts are arranged, and has a length longer than the horizontal width of the line head. This means that after all the steps described below have been completed, the head substrate 10 is cut in the same manner from the opposite side of the groove by using a dicing saw,
This is performed to make the ejection member 12 protrude from the head substrate 10.

After forming a groove in the head substrate 10, a metal such as Al or Ni is coated on the head substrate 10 by about 1 μm by sputtering.
m, a photoresist is applied, and the photoresist layer is exposed through a photomask having a predetermined electrode pattern. Thereafter, development is performed to form a photoresist pattern, and an electrode pattern is formed by etching.
Here, the width of the electrode is 10 to 50 μm.

Next, a thickness of 20
A polyimide film of about 50 μm is stuck with a laminator. As in the case of forming the electrode pattern, a desired partition pattern and a guide member pattern are formed by etching using a photoresist and a photomask.
Here, the width of the discharge member is about 20 to 50 μm, and the interval between the discharge members is about 150 to 500 μm. The ink flow path between the partition and the ejection member is about 10 to 50 μm.

Next, the head substrate is placed in a plating bath made of Ni or the like, and a current is supplied to the electrode pattern to deposit a metal layer by plating up to the height of the partition wall pattern and the guide member. Thereafter, a polyimide film having a thickness of about 20 to 50 μm is adhered thereon again with a laminator, and the ink inlet 1 is formed using a photoresist and a photomask in the same manner as in the previous step.
An insulating layer 14 having a 7 and a V-shaped cut 15 is manufactured. Finally, a groove is formed by a dicing saw from the back surface of the head substrate 10 along the groove on the front surface, the head substrate 10 is folded at that portion, and the folded surface is polished obliquely to complete.

The head substrate 1 manufactured by the above steps
When a lid 19 having an ink flow path formed thereon is bonded to the upper side of 0, a head as shown in FIG. 1 is completed.

Next, the structure of the lid 19 in which the ink flow path is formed will be described with reference to FIGS.

FIG. 8 is a top view of the head viewed from the lid 19 side. A pipe 25 for supplying ink and a pipe 26 for discharging ink are connected to the lid 19. FIG. 9 shows an overview of the connection between the pipes 25 and 26 and the lid 19.

FIG. 9A shows a section taken along a dotted line AA 'in FIG. 8, and FIG. 9B shows a section taken along a dotted line BB' in FIG.
The pipes 25 and 26 have an inner diameter of about 2 mm. Since the ink flow path in the head section is considerably thinner than 2 mm and the ink discharge section is wide in the width direction, the ink flow path is provided so as to gradually narrow in the height direction and widen in the width direction. By gradually changing the size of the flow path, the ink can be circulated without stagnation. Eliminating the stagnation of the ink makes it possible to prevent sedimentation of the pigment in the ink, thereby preventing clogging of the ink circulation system.

FIG. 10A shows a cross section taken along a dotted line dd 'in FIG. 9, and FIG. 10B shows a cross section taken along a dotted line ee' in FIG. The reason for adopting such a structure is to provide the ink supply system and the ink recovery system so that the flow paths thereof do not overlap. The ink supply system and the ink recovery system are located on the right side of the dotted line cc 'in FIG. The ink flow path is divided into upper and lower parts and the ink flow path is expanded in the width direction of the head on the left side of cc '.

In the head manufactured as described above, the distance between the ink discharge portions (the distance between the guide members) is 150 to 500 μm.
m, it is difficult to obtain a high-definition image. If the interval between the ink ejection portions is smaller than 150 μm, the ink ejection direction is bent because the electric field distribution is disturbed by the influence of the pulse voltage applied to the adjacent electrodes even if the ink flow paths are individualized. Problems arise. FIG. 7 shows a method for solving such a problem.

FIG. 7 shows the line head shown in FIG. The three steps are an example, and the number n of steps is a desired dot interval d1 during printing and an interval d2 between the guide members 12.
And d2 = d1 × n. The n-stage line heads are overlapped so that the guide members are arranged in a staggered manner so that dots can be printed at a desired pitch in the direction perpendicular to the recording medium transport direction. In this manner, high-definition images can be recorded at high speed by printing by overlapping the line heads.

FIG. 1 shows the ink circulation in this configuration.
3 will be described.

FIG. 13 is a cross-sectional view of the line head shown in FIG. The configuration is a configuration in which the configuration shown in FIG. 1 is overlapped. The circulation of the ink is configured to branch into n stages from the pipe 25 of the ink supply system, supply the ink to each line head, collect the ink circulated in each line head, and collect the ink from the pipe 26 of the ink recovery system. .

With the above arrangement, the dot interval in the direction perpendicular to the recording medium transport direction during printing can be reduced, and the recording medium transport direction can be adjusted to a high definition by adjusting the dot printing cycle and the recording transport speed. It is possible to realize a recording device capable of printing a simple image.

Therefore, according to the present invention, the ink flow path is individualized for each channel by surrounding the ejection member with the partition wall, and the potential applied to the recording electrode of the channel for ejecting the ink is transmitted to the surrounding channels through the ink. Can be prevented. For this reason, there is an effect that a high-definition image can be recorded without being affected by the adjacent recording electrodes, the ink ejection direction is stable, and the image is not disordered.

Further, by flowing the ink from the root of the ejection member toward the tip end of the individualized ink flow path and returning the ink toward the root just before the flight point,
A force for drawing the dark ink into the circulation portion from the tip of the ejection member is generated, so that new ink is constantly supplied to the tip of the ejection member, thereby preventing the ink from sticking at the tip of the ejection member. Therefore, since the fixed matter does not adhere to the tip of the discharge member, the ink discharge direction is a predetermined direction, and there is an effect that a high-definition image without image disturbance can be recorded.

Further, by arranging heads having an ink circulation system in which the ink discharge sections are distributed in a staggered manner, the number of dots per unit area on the recording medium can be increased,
There is an effect that a high-definition image can be recorded at high speed.

[0057]

In other words, the present invention can provide an ink jet recording apparatus which can prevent ink from sticking to the tip of the recording electrode and can obtain a high-definition image without shifting the ink landing position due to the shift of the ejection point.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of an ink jet head of the present invention.

FIG. 2 is a view showing one embodiment of a cross section of the ink jet head of the present invention.

FIG. 3 is a view showing another embodiment of the cross section of the ink jet head of the present invention.

FIG. 4 is a view showing one embodiment of an ink jet recording apparatus according to the present invention.

FIG. 5 is a diagram showing an ink circulation system of the inkjet head of the present invention.

FIG. 6 is a diagram illustrating a method for adjusting the ink pressure of the ink circulation system according to the present invention.

FIG. 7 is a view showing another embodiment of the ink jet head of the present invention.

FIG. 8 is a diagram showing one embodiment of the upper surface of the ink jet head of the present invention.

FIG. 9 is a view showing one embodiment of a cross section of the ink jet head of the present invention.

FIG. 10 is a diagram showing one embodiment of a cross section of the ink jet head of the present invention.

FIG. 11 is a diagram illustrating circulation of ink flowing to a discharge member according to the present invention.

FIG. 12 is a diagram illustrating a state of an ink meniscus formed in an ink ejection unit of the present invention.

FIG. 13 is a diagram showing a cross section of another embodiment of the ink jet head of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Housing, 2 ... Recording head, 3 ... Ink tank, 4 ... Ink circulation system, 5 ... Ink ejection part, 6 ... Common electrode, 7 ... Recording medium, 8 ... Recording medium conveyance path, 9 ... Recording medium conveyance device,
DESCRIPTION OF SYMBOLS 10 ... Head board, 11, 11a, 11b, 11c ... Recording electrode, 12, 12b, 12c ... Discharge member, 13 ... Partition wall, 14 ... Insulating layer, 15, 15b, 15c ... V-shaped cut, 17 ... Ink flow Inlet, 18: ink meniscus, 19: lid, 21: ink pool, 22a, 22b ...
Pumps, 23, 25, 26, 27: piping, 24: ink flow rate adjustment chamber, 32: ink level detector.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshinobu Fukano 7-1-1, Omikacho, Hitachi City, Ibaraki Prefecture Inside Hitachi, Ltd. Hitachi Research Laboratory, Ltd. (72) Inventor Shigetaka Fujiwara 7-1, Omikamachi, Hitachi City, Ibaraki Prefecture No. 1 Hitachi, Ltd. Hitachi Research Laboratory (72) Inventor Atsushi Onose 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-term in Hitachi Research Laboratory Hitachi, Ltd. AF30 AF33 AG29 AG92 AG93 AH07 BD06

Claims (6)

[Claims] 1. A substrate, a discharge member disposed on the substrate, a recording electrode disposed to sandwich the discharge member, for discharging ink from the discharge portion, and a covering portion including the recording electrode. An ink jet recording head, wherein the ink is supplied from the base of the ejection member and is collected upward from near the tip of the ejection member. 2. The ink jet recording head according to claim 1, wherein the height of the covering portion is higher than the height of a discharge member. 3. The ink jet recording head according to claim 1, wherein an inlet of a flow path for collecting ink from near a tip of said discharge member has a V-shape. 4. A substrate, a discharge member disposed on the substrate, a recording electrode disposed to sandwich the discharge member, for discharging ink from the discharge portion, and a covering portion including the recording electrode. An ink supply path for supplying the ink to the discharge member, and an ink recovery path for recovering ink from near the tip of the discharge member. An inkjet recording head that gradually narrows as it approaches the member. 5. A substrate, a discharge member disposed on the substrate, a recording electrode disposed to sandwich the discharge member, for discharging ink from the discharge portion, and a covering portion including the recording electrode. And a recording head having a circulating unit for circulating the ink, an ink chamber for storing the ink, a common electrode arranged to face the ejection member, and an inkjet having a transport path for transporting a recording medium. Recording device. 6. The ink jet recording apparatus according to claim 5, wherein the recording head has the ejection members arranged in a staggered manner.
In addition, an ink jet recording apparatus configured by stacking several stages.