JP2002001966A - Recording head, its manufacturing method, and ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a good quality picture consistently by jetting ink under stable conditions preventing an ink reservoir potion from generating a staying portion of bubbles. SOLUTION: In forming a nozzle substrate 12 by plural times electrocastings, after a nozzle hole 23 to jet ink drips to a first layer 21 is formed, a nozzle communication hole 24 communicating with the nozzle hole 23 in a second layer 22 is set at 90 deg. or larger from the first layer 21 and formed into a shape tapered toward the nozzle hole 23, and the interface of the inner peripheral face of the nozzle hole 23 and the nozzle communication hole 24 of each layer which forms the nozzle hole 23 and the nozzle communication hole 24, respectively, is formed to have no gap for preventing bubbles from staying in the nozzle communication hole 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head for printing by ejecting ink droplets from nozzles, a method of manufacturing the recording head, and an ink jet recording apparatus.

[0002]

2. Description of the Related Art An electrostatic type recording head used in an ink jet recording apparatus is disclosed in, for example, Japanese Patent Application Laid-Open Nos. 5-50601, 9-39229 and 9-392.
No. 35, etc., a voltage is applied between a diaphragm provided at a certain interval on a diaphragm provided on one surface of a pressurized liquid chamber having a nozzle, and a diaphragm is applied to the diaphragm. The ink is deformed by electrostatic attraction or repulsion toward the side, and the ink in the pressurized liquid chamber is ejected from the nozzles to print on the recording paper. This electrostatic type recording head has the advantages of being thin, capable of performing high-density, high-quality printing, and having a long service life.

When manufacturing a nozzle substrate having the nozzles of this recording head, for example, as shown in JP-A-5-4346 and JP-A-7-156389, two or more layers are formed by electroforming. are doing. Forming a plurality of layers by electroforming in this manner is performed by forming a predetermined gap between the nozzle and the diaphragm provided opposite to each nozzle hole, forming a pressurized liquid chamber for filling ink, and forming the pressurized liquid. This is for forming an ink supply groove for supplying ink to the chamber.

A conventional manufacturing method of manufacturing a nozzle substrate by forming a plurality of layers by electroforming will be described with reference to the process chart of FIG. As shown in FIG. 8A, a positive type resist is applied to a master substrate 30 made of a conductive substrate such as a stainless steel plate, exposed and developed, and a predetermined shape, for example, having a diameter of 80 μm.
After forming a circular pattern 31 having a thickness of 1 μm and a thickness of 1 μm, 30 μm of Ni is deposited on the surfaces of the master substrate 30 and the circular pattern 31 by electroforming in, for example, a Ni electroforming solution to form the first layer 2.
Form one. At this time, the first layer 21 has a circular pattern 31.
Therefore, the nozzle hole 23 having a diameter of about 20 μm is formed. Next, as shown in FIG. 8B, a positive resist is applied on the first layer 21, exposed and developed, and a communication hole pattern 41 for forming a nozzle communication hole communicating with the nozzle hole 23 and ink are formed. A supply groove pattern 42 for forming a supply groove is formed. Next, as shown in FIG. 8C, Ni is deposited on the first layer 21, the communication hole pattern 41, and the supply groove pattern 42, for example, by 25 μm by Ni electroforming to form the second layer 22. Thereafter, the master substrate 30 is released from the first layer 21, and the circular pattern 31, the communication hole pattern 41, and the supply groove pattern 42 are separated and removed, thereby completing the nozzle substrate 43.

Another manufacturing method for manufacturing a nozzle substrate is as shown in FIG.
Then, a positive resist is applied, exposed and developed to form a circular pattern 31 of a predetermined shape, and then Ni is applied to the surfaces of the master substrate 30 and the circular pattern 31 by Ni electroforming.
The first layer 21 is formed by depositing μm. Next, FIG.
As shown in (b), a thickness of, for example, 30 μm is formed on the first layer 21.
m dry film resist (hereinafter referred to as negative DF)
R) is laminated by a thermocompression roller, and a communication hole pattern 44 for forming a nozzle communication hole communicating with the nozzle hole 23 and a supply groove pattern 45 for forming an ink supply groove are formed by using a photolithography technique. Next, as shown in FIG. 9C, a second layer 22 is formed on the first layer 21 by depositing Ni by, for example, 25 μm by Ni electroforming. Thereafter, the master substrate 30 is released from the first layer 21, and the circular pattern 31, the communication hole pattern 43, and the supply groove pattern 44 are separated and removed, thereby completing the nozzle substrate 46.

The nozzle substrate 43 manufactured as described above,
In order to improve the ejection characteristics of the ink droplets by the recording head using the nozzle 46, it is necessary to increase the hydrophilicity between the nozzle hole 23 or the nozzle communication hole and the ink on the inner surface of the ink supply groove. It is necessary that the surface located at the outer peripheral portion of the nozzle where the ink is formed has high water repellency with ink. Therefore, a water-repellent layer is formed on the surface of the nozzle substrate on the ink ejection side. A method for manufacturing the nozzle substrate having the water-repellent layer formed thereon will be described with reference to the process chart of FIG.

As shown in FIG. 10A, a positive resist is applied to the master substrate 30, exposed and developed to form a circular pattern 31 of a predetermined shape. Ni on the surface of the circular pattern 31
The first layer 21 is formed by depositing 30 μm. Next Figure 10
As shown in (b), the first layer 21 is released from the master substrate 30, and the circular pattern 31 is peeled off. Next, as shown in FIG. 10C, a negative DFR having a thickness of, for example, 70 μm is placed on the lower surface of the first layer 21 opposite to the circular portion formed by the circular pattern 31 by a thermocompression roller (temperature: 60 ° C.). And a negative type DFR is sunk into the nozzle hole 23 to form a resist layer 47. FIG.
As shown in (d), a thickness of, for example, 20
A resist layer 48 is formed by laminating a negative type DFR having a thickness of μm using a thermocompression roller (temperature of 60 ° C.).
Is sandwiched between the resist layers 47 and 48,
The entire surface is exposed from the lower side of the resist layer 47 side. Thereafter, by performing development and rinsing, as shown in FIG. 10E, the resist layer 47 on the lower surface of the first layer 21 exposed to light and the cylindrical resist portion 49 protruding from the nozzle hole 23 remain. I do. Next, in an electroforming solution of Ni containing particles of a fluororesin, for example, polytetrafluoroethylene (hereinafter, referred to as PTFE), by electrolytic eutectoid plating,
PTFE-N only on the upper surface (ink ejection surface) of the first layer 21
An i-layer water-repellent layer 50 is formed. After that, the resist layer 47
Then, the resist portion 49 is peeled off from the first layer 21 and washed, and heat treatment is performed at 350 ° C. for 1 hour, for example, to form a water-repellent layer 50 exhibiting good water repellency on the discharge surface other than the nozzle holes.

[0008]

However, the nozzle substrate 43 manufactured by the manufacturing method shown in the process diagram of FIG. 8 has a Ni plating layer over the communication hole pattern 41 and the supply groove pattern 42 when the second layer 22 is formed. Because of the hang, the space 5 having the thickness of the communication hole pattern 41 and the supply groove pattern 42 is provided at the end face of the second layer at the interface between the first layer 21 and the second layer 22.
There is one. Since such a space 51 does not generate a flow of ink when filled with ink after being assembled as a recording head, there is a high risk that the space 51 will contain bubbles. Further, even when the ink is filled so as to eliminate bubbles by vacuum filling or the like, there is a risk that bubbles mixed in the supplied ink may stay in the space 51. Such air bubbles act to reduce the ink pressure and act as a source of gas cavitation in a series of operations for operating the vibration plate to increase the ink pressure and discharge the ink from the nozzles. Gas cavitation is also referred to as aeration, and means that bubbles in a liquid are subjected to repeated pressurization and depressurization to take in a gas dissolved in the liquid, grow, and decompose. Reducing the pressure generated by the operation of the vibrating plate reduces the discharge speed and discharge amount of ink droplets, degrades print quality, and in extreme cases, may hinder the discharge of ink droplets themselves.

The nozzle substrate 46 manufactured by the manufacturing method shown in the process diagram shown in FIG. 9 has bubbles at the interface between the first layer 21 and the second layer 22 like the nozzle substrate 46 manufactured in FIG. Although there is no stagnation, since the nozzle communication hole 52 formed in the second layer 22 rises vertically from the surface of the first layer 21, when forming the water-repellent layer 50 on the nozzle substrate 46, There is such a problem. That is, FIG.
As shown in FIG. 11A, after the nozzle substrate 46 is manufactured, as shown in FIG.
When the negative DFR 53 is laminated from the lower surface on the side opposite to the discharge surface of the nozzle substrate 46 by a thermocompression bonding roller, the bubbles existing in the nozzle holes 23 and the nozzle communication holes 52 are displaced in the nozzle hole direction A and the nozzle communication hole direction B. It is desirable that the liquid is completely discharged from two directions. However, since the nozzle communication hole 52 rises vertically from the surface of the first layer 21, exhaust from the nozzle communication hole direction B is not sufficiently performed, and the negative DFR 53 is laminated and a resist is formed on the lower surface of the first layer 21. When the layer 47 is formed, the bubble portion 54 remains near the interface between the first layer 21 and the second layer 22, as shown in FIG. In this state, a resist layer 48 is formed on the discharge surface of the nozzle substrate 46, and when the entire surface is exposed from the resist layer 47 side on the lower surface of the first layer 21, as shown in FIG. Scattered light is generated and proceeds in a direction opposite to the bubble portion 54 of the nozzle hole 23. Thereafter, when development and rinsing are performed, as shown in FIG.
The resist layer 47 on the lower surface of the first layer 21 exposed to the light and the cylindrical resist portion 49 protruding from the nozzle hole 23 are formed, but the formed resist portion 49 is scattered by the remaining bubbles 54. An area larger than the nozzle hole 23 remains in the portion 55 where the light has entered. Then, FIG.
As shown in FIG. 11 (g), when a water-repellent layer 50 is formed on the surface of the first layer 21, the resist layer 47 and the resist part 49 are peeled off, washed and heat-treated, as shown in FIG. A portion without the water-repellent layer 50 is formed in a portion 55 of the outer periphery of the portion 23 where the light scattered by the bubble portion 54 is incident. As described above, when the water-repellent layer 50 is not locally located on the outer peripheral portion of the nozzle hole 23 and is in a hydrophilic state, when the ink droplets are ejected, the ink becomes The droplets are attracted to cause a defective ejection bend, so that stable ejection characteristics cannot be obtained. This phenomenon is negative DFR5
In addition to the case where No.3 is used, a similar problem occurs when a photosensitive material such as a liquid resist is filled.

According to the present invention, it is possible to improve the disadvantages of the present invention, and to stably eject ink by preventing the generation of bubbles in the ink storage portion, and to form a uniform water-repellent layer on the surface of the ink ejection side. It is an object of the present invention to provide a recording head, a method for manufacturing the recording head, and an ink jet recording apparatus capable of forming a recording head, ejecting ink with stable ejection characteristics, and stably forming a high-quality image.

[0011]

A recording head according to the present invention forms a nozzle hole for discharging ink droplets on a first layer by electroforming a plurality of times, and then forms a nozzle hole on the second layer and thereafter. A nozzle substrate having a nozzle communication hole formed therein and a diaphragm substrate are laminated, a pressurized liquid chamber communicating with the nozzle is formed by the nozzle substrate and the diaphragm substrate, and a diaphragm is provided on one surface of the pressurized liquid chamber. In a recording head that displaces the diaphragm and discharges ink in the pressurized liquid chamber from the nozzle, the nozzle communication hole of the nozzle substrate rises at an angle of 90 degrees or more from the first layer and has a tapered shape with respect to the nozzle hole. In addition, there is no gap at the interface between the nozzle hole of each layer forming the nozzle hole and the nozzle communication hole and the inner peripheral surface of the nozzle communication hole.

It is desirable that the first layer having the nozzle holes of the nozzle substrate has a water-repellent layer on at least the ink ejection surface side including the outer periphery of the nozzle holes.

A method of manufacturing a recording head according to the present invention comprises:
After forming a nozzle hole for ejecting ink droplets on the first layer by electroforming a plurality of times, a nozzle substrate and a diaphragm substrate on which a nozzle communication hole communicating with the nozzle hole is formed on the second and subsequent layers are laminated. A pressurized liquid chamber communicating with the nozzle is formed by the nozzle substrate and the vibration plate substrate, and a vibration plate is provided on one surface of the pressurized liquid chamber,
In a method for manufacturing a recording head in which a diaphragm is displaced and ink in a pressurized liquid chamber is ejected from a nozzle, a nozzle communication hole of a nozzle substrate is raised from the first layer at an angle of 90 degrees or more and has a tapered shape with respect to the nozzle hole. And the nozzle hole of each layer forming the nozzle communication hole and the nozzle communication hole is formed such that there is no gap between the interfaces of the inner peripheral surfaces of the nozzle communication hole.

In the first layer of the nozzle substrate, a round-shaped nozzle hole is formed at the opening end on the surface on which the second layer is formed, and the opening end of the nozzle communication hole formed in the second and subsequent layers is formed as a nozzle hole. It is good to form in the round shape following the round shape of the opening end of this.

In the first layer of the nozzle substrate, a round-shaped hole is formed at the opening end on the side where the second layer is formed, and the opening end of the first layer is formed on the inner peripheral surface of the round-shaped hole. The second and subsequent layers may be formed to form a nozzle communication hole in which the nozzle hole and the opening end are round.

Further, it is desirable to form a water-repellent layer on the ink ejection surface side including at least the outer periphery of the nozzle hole of the first layer in which the nozzle hole is formed.

An ink jet recording apparatus according to the present invention has a recording head manufactured by the above-described manufacturing method.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a recording head according to the present invention, a nozzle substrate, a diaphragm substrate and an electrode substrate are joined and laminated. A plurality of nozzles are provided in an array on the nozzle substrate. In this recording head, a pressurized liquid chamber and a fluid resistance path communicating with each nozzle are formed by a nozzle substrate and a diaphragm substrate for each nozzle, and the fluid resistance path communicates with a common liquid chamber.
A vibrating plate is provided on one surface of the pressurized liquid chamber. Individual electrodes are provided on the electrode substrate so as to face the vibration plate, and FPCs, which are printed wiring boards, are connected to the individual electrodes via contact portions.

A nozzle substrate having a nozzle is formed in a plurality of layers, for example, two layers of a first layer and a second layer by electroforming a plurality of times, and after forming a nozzle hole for discharging ink droplets in the first layer. The second layer has an ink supply groove that forms a fluid resistance path with the nozzle communication hole that communicates with the nozzle hole. The shape of the nozzle communication hole is tapered with respect to the nozzle hole. The interface between the first layer and the second layer on the inner peripheral surface of the nozzle hole and the nozzle communication hole is formed such that there is no gap.

When manufacturing this nozzle substrate manufacturing method, a positive type resist is applied to a position corresponding to each nozzle of a master substrate made of a conductive material such as a stainless steel plate, and exposed and developed to form a predetermined shape. Is formed. A first layer is formed on the surface having the circular pattern by depositing Ni plating to a predetermined thickness by, for example, Ni electroforming. At this time, the Ni plating overhangs a certain amount in a circular pattern to form a nozzle hole having a constant diameter and a round opening end. Next, after laminating an electroformed mask material, for example, a negative type dry film resist (hereinafter, referred to as a negative type DFR) with a thermocompression bonding roller, a nozzle communication hole communicating with the nozzle hole is formed by using a photolithography technique. The communication hole pattern and the supply groove pattern forming the ink supply groove are patterned. At this time, the communication hole pattern and the supply groove pattern are patterned in a reverse taper shape. Next, using the communication hole pattern and the supply groove pattern as a mask, Ni is formed on the surface of the first layer by electroforming.
A second layer is formed by depositing plating to a constant thickness. Thereafter, the first layer is released from the master substrate, and the circular pattern, the communication hole pattern, and the supply groove pattern are peeled off to complete the nozzle substrate.

[0021]

FIG. 1 is a block diagram of one embodiment of the present invention.
As shown in the figure, an ink jet printer 1 includes four ink cartridges 2 each containing ink of each color of cyan C, magenta M, yellow Y, and black Bk,
Four recording heads 3 each having a plurality of nozzles and supplied with ink from each ink cartridge 2, a carriage 4 on which the ink cartridge 2 and the recording head 3 are mounted, and paper feed trays 5a, 5b containing recording paper, It has a transport roller 8 for transporting recording paper from the manual feed table 6 to the printing unit 7, and a discharge roller 10 for discharging the printed recording paper to a discharge tray 9. When printing the image data sent from the host device on the recording paper, the carriage 4 scans along the carriage guide roller 11 while the nozzles of the recording head 3 print on the recording paper sent to the printing unit 7 by the transport rollers 8. And ejects ink according to the image data to record characters and images.

The recording head 3 is shown in an exploded perspective view of FIG.
As shown in the sectional view of FIG.
3 and the electrode substrate 14 are bonded and laminated by an adhesive or anodic bonding. The nozzle substrate 12 is provided with a plurality of nozzles 15 in an array. The recording head 3 forms, for each nozzle 15, a pressurized liquid chamber 16 and a fluid resistance path 17 communicating with the nozzle 15 by the nozzle substrate 12 and the diaphragm substrate 13, and the fluid resistance path 17 communicates with a common liquid chamber 18. are doing. A vibrating plate 19 is provided on one surface of the pressurized liquid chamber 16. Individual electrodes 20 are provided on the electrode substrate 14 so as to face the vibration plate 19, and an FPC, which is a printed wiring board, is connected to each individual electrode 20 via a contact portion.

The nozzle substrate 12 having the nozzle 15 is formed of a plurality of layers by electroforming a plurality of times, for example, as shown in a sectional view of FIG. 4, two layers of a first layer 21 and a second layer 22.
After a nozzle hole 23 for discharging ink droplets is formed in the layer 21, a nozzle communication hole 24 communicating with the nozzle hole 23 and an ink supply groove 25 forming the fluid resistance path 17 are formed in the second layer 22. The shape of the nozzle communication hole 24 is the nozzle hole 2
3 is tapered. In addition, the nozzle hole 23
Layer 21 and second layer 22 on the inner peripheral surface of nozzle communication hole 24
Are formed such that there is no gap at the interface.

The method for manufacturing the nozzle substrate 12 will be described with reference to the process chart of FIG. As shown in FIG. 5A, the nozzle holes 23 and the nozzle communication holes 2 of the nozzle substrate 12 of the master substrate 30 made of a conductive material such as a stainless steel plate are provided.
A positive resist is applied to the position corresponding to the nozzle 15 having the nozzle 4 and exposed and developed to a predetermined shape, for example, 80 μm in diameter.
A circular pattern 31 having a thickness of 1 μm and a thickness of 1 μm is formed. The first layer 21 is formed on the surface having the circular pattern 31 by, for example, depositing Ni plating to a predetermined thickness of 30 μm, for example, in a Ni electroforming solution by electroforming. At this time, since the Ni plating overhangs the circular pattern 31 by about 30 μm, the nozzle hole 23 having a diameter of about 20 μm is formed. Next, as shown in FIG. 5B, an electroformed mask material, for example, a negative type dry film resist (hereinafter, referred to as a negative type DFR) having a thickness of 30 μm was laminated on the first layer 21 by a thermocompression roller. Thereafter, the communication hole pattern 32 for forming the nozzle communication hole 24 by using a photolithography technique.
And the supply groove pattern 33 that forms the ink supply groove 25 is patterned. At this time, the communication hole pattern 32 and the supply groove pattern 33 are patterned in a reverse taper shape. Next, as shown in FIG.
The second layer 22 is formed by depositing, for example, 25 μm of Ni plating on the surface of the first layer 21 by electroforming using the 2 and the supply groove pattern 33 as a mask. When the second layer 22 of Ni plating is formed by electroforming, a negative DFR is used as an electroforming mask material, but a thick film resist may be used. A liquid thick film resist is advantageous for forming a fine pattern, but a negative DFR is advantageous in terms of handling and cost. Thereafter, as shown in FIG. 5D, the first layer 21 and the second layer 22 are released from the master substrate 30,
The nozzle substrate 12 is completed by peeling and removing the circular pattern 31, the communication hole pattern 32, and the supply groove pattern 33.

As described above, the second layer 22 is formed by depositing Ni plating on the surface of the first layer 21 by electroforming.
The formation of a gap at the interface between the layer 21 and the second layer 22 can be prevented. In addition, by forming the second layer 22 using the circular pattern 31 formed on the surface of the communication hole pattern 32 and having a reverse taper shape as a mask, the second layer 22 is tapered toward the nozzle hole 23 and becomes the first layer. The nozzle communication hole 24 that rises from 21 to an angle of 90 degrees or more can be formed. When the recording head 3 is manufactured using the nozzle substrate 12 and filled with ink, the ink passing through the fluid resistance path 17 flows through the ink supply groove 25 having an open end at an angle of 90 degrees or more. Bubbles can be prevented from staying in the fluid resistance path 17. In addition, since there is no gap at the interface between the first layer 21 and the second layer 22 and the nozzle communication hole 24 is tapered toward the nozzle hole 23 and rises from the first layer 21 at an angle of 90 degrees or more. Bubbles can be prevented from staying in the nozzle communication holes 24. Therefore, when the ink is ejected from the nozzle 15, the ink can be ejected at a stable ejection pressure without being affected by the bubbles, and the fluctuation of the ejection speed and the ejection amount of the ink droplet can be prevented, and the high quality printing can be stably performed. You can do it.

Further, in order to form a water-repellent layer on the discharge surface on the surface of the first layer 21, when laminating the negative type DFR on the lower surface of the second layer 22, the nozzle communication holes 24 are formed in the first layer 21.
Since it rises at an angle of 90 degrees or more, air bubbles can be stably discharged from the nozzle communication hole 24,
A uniform water-repellent layer can be formed on the outer peripheral surface of the nozzle hole 23 by preventing the formation of air bubbles in the nozzle communication hole 24, and the ink can be discharged with stable discharge characteristics.

Next, a second method for manufacturing the nozzle substrate 12 will be described with reference to the process chart of FIG. As shown in FIG. 6A, a positive resist is applied to a position corresponding to a nozzle 15 having a nozzle hole 23 and a nozzle communication hole 24 of a nozzle substrate 12 of a master substrate 30 made of a conductive material such as a stainless steel plate. Then, exposure and development are performed to form a circular pattern 31 having a predetermined shape, for example, a diameter of 80 μm and a thickness of 1 μm. On the surface having the circular pattern 31, for example, Ni
In an electroforming solution, Ni plating is applied to a predetermined thickness by electroforming, for example.
The first layer 21 is formed by depositing 30 μm. At this time, Ni
Since the plating overhangs the circular pattern 31 by approximately 30 μm, the nozzle hole 23 having a diameter of about 20 μm is formed. Next, as shown in FIG. 6B, an electroformed mask material, for example, a negative DFR having a thickness of 30 μm is laminated on the first layer 21 by a thermocompression roller, and then, using a photolithography technique, The communication hole pattern 32 and the supply groove pattern 33 are patterned. At this time, the communication hole pattern 32 is formed on the round shape of the first layer 21. The communication hole pattern 32 and the supply groove pattern 33 may have a vertical shape, but are preferably formed in an inverted tapered shape. Next, as shown in FIG. 6C, Ni plating is deposited on the surface of the first layer 21 by, for example, 25 μm by electroforming using the communication hole pattern 32 and the supply groove pattern 33 as a mask to form the second layer 2.
Form 2 The upper opening end of the portion of the formed second layer 22 using the communication hole pattern 32 as a mask is the first layer 21.
The round shape reflects the round shape. Thereafter, as shown in FIG. 6D, the first layer 21 and the second layer 22 are formed.
Is released from the master substrate 30 to form a circular pattern 31.
Then, the communication hole pattern 32 and the supply groove pattern 33 are peeled and removed to complete the nozzle substrate 12.

As described above, the communication hole pattern 32 is formed on the first layer 2.
1 is formed on the round shape, and the opening end of the nozzle communication hole 24 communicating with the nozzle hole 23 formed in the second layer 22 is formed in a round shape. A shape having a low retention probability can be formed, and a uniform water-repellent layer can be formed on the ejection surface on the surface of the first layer 21.

Next, a third manufacturing method of the nozzle substrate 12 will be described with reference to the process chart of FIG. As shown in FIG. 7A, a positive resist is applied to a position corresponding to the nozzle 15 having the nozzle hole 23 and the communication hole 24 of the nozzle substrate 12 of the master substrate 30 made of a conductive material such as a stainless steel plate. Exposure and development, the first manufacturing method and the second
A circular pattern 34 having a diameter larger than that of the circular pattern 31 formed by the manufacturing method described above, for example, 130 μm in diameter and 1 μm in thickness is formed. The first layer 21 is formed on the surface having the circular pattern 34 by, for example, depositing Ni plating to a predetermined thickness of 30 μm, for example, in a Ni electroforming solution by electroforming. At this time, the Ni plating is approximately 30 μm on the circular pattern 31.
The hole 3 has a diameter of about 70 μm
5 are formed. Next, as shown in FIG. 7B, an electroformed mask material, for example, a negative type DFR having a thickness of 30 μm is laminated on the first layer 21 by a thermocompression roller, and then, using a photolithography technique, A supply groove pattern 33 for forming the ink supply groove 25 is formed. Next Figure 7
As shown in (c), Ni plating is applied to the surface of the first layer 21 by electroforming, for example, using the supply groove pattern 33 as a mask.
The second layer 22 is formed by depositing μm. At this time, since the electroformed mask material does not exist in the hole 35 of the first layer 21, Ni plating is continuously performed on the hole 35 of the first layer 21 to form the second layer 22. The hole 35 has N
i-plate overhangs 25μm and nozzle diameter is about 20μ
m nozzle holes 23 are formed, and the upper open end of the second layer 22 has a round shape reflecting the round shape of the first layer 21. Thereafter, as shown in FIG.
The first and second layers 22 are released from the master substrate 30, and the circular pattern 34 and the supply groove pattern 33 are peeled off to complete the nozzle substrate 12.

As described above, by continuously plating the portion of the hole 35 of the first layer 21 with Ni to form the second layer 22, the shape of the nozzle communication hole 24 communicating with the nozzle hole 23 is changed. 23 can be formed into a horn shape that is tapered, and the discharge performance of air bubbles mixed in the ink can be improved, and a uniform water-repellent layer can be formed on the ejection surface of the surface of the first layer 21. .

As described above, it is possible to improve the discharging performance of bubbles mixed in the ink and to form a uniform water-repellent layer on the ejection surface of the surface of the first layer 21. Can be manufactured stably, and by using this recording head 3 in an image forming apparatus such as the ink jet printer 1, a high density image can be formed with stable ejection characteristics.

Although the above-described embodiment has been described with respect to the recording head 3 of the electrostatic type, it can be similarly applied to a recording head using a piezoelectric element or a recording head of a bubble jet (registered trademark) type.

[0033]

As described above, according to the present invention, after a nozzle hole for discharging ink droplets is formed in the first layer by electroforming a plurality of times, the nozzles communicating with the nozzle holes in the second and subsequent layers are formed. When forming the communication hole, the nozzle communication hole is formed from the first layer.
Formed at an angle of 90 degrees or more to the rising nozzle hole and formed so that there is no gap at the interface between the nozzle hole of each layer forming the nozzle hole and the nozzle communication hole and the inner peripheral surface of the nozzle communication hole As a result, it is possible to prevent bubbles from staying in the nozzle communication holes, and to discharge ink at a stable discharge pressure without being affected by bubbles when discharging ink from the nozzles, and to discharge ink droplets at a stable speed. High-quality printing can be stably performed by preventing fluctuations in the amount.

When the water-repellent layer is formed on the discharge surface on the surface of the first layer, the nozzle communication holes formed in the second and subsequent layers rise from the first layer at an angle of 90 ° or more.
When masking the nozzle hole and the nozzle communication hole, the air bubbles in the nozzle communication hole can be stably discharged, and a uniform bubble is formed on the outer peripheral surface of the nozzle hole on the discharge surface by preventing the formation of air bubbles in the nozzle communication hole. A water-repellent layer can be formed, and ink can be ejected with stable ejection characteristics.

Further, the first layer of the nozzle substrate has a round nozzle opening on the side of the surface on which the second layer is formed, and the opening end of the nozzle communication hole formed on the second layer and the subsequent layers has a nozzle shape. By forming a round shape following the round shape of the opening end of the hole, it is possible to prevent bubbles from staying in the nozzle communication hole, and to form a water-repellent layer on the discharge surface on the surface of the first layer. Furthermore, the performance of discharging air bubbles from the nozzle communication holes when masking the nozzle holes and the nozzle communication holes can be further improved.

In the first layer of the nozzle substrate, a round-shaped hole is formed at the opening end of the second-layer forming surface, and the opening end of the first layer is formed at the inner peripheral surface of the round-shaped hole. By forming the second layer and the subsequent layers to form a nozzle communication hole having a round nozzle opening and an open end, the nozzle hole and the nozzle communication hole can be formed in a continuous horn shape, thereby improving the bubble discharging performance. Can be enhanced.

Further, by using a recording head having a nozzle substrate with improved bubble discharging performance in a recording apparatus such as an ink jet printer, a copying machine, a facsimile, etc., ink droplets are ejected from the nozzles with stable ejection characteristics. And a high-quality image can be stably formed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an ink jet printer according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view illustrating a configuration of a recording head.

FIG. 3 is a cross-sectional view illustrating a configuration of a recording head.

FIG. 4 is a cross-sectional view illustrating a configuration of a nozzle substrate.

FIG. 5 is a process chart showing a method for manufacturing a nozzle substrate.

FIG. 6 is a process chart showing a second method for manufacturing a nozzle substrate.

FIG. 7 is a process chart showing a third method for manufacturing a nozzle substrate.

FIG. 8 is a process chart showing a conventional method for manufacturing a nozzle substrate.

FIG. 9 is a process chart showing a second conventional method for manufacturing a nozzle substrate.

FIG. 10 is a process chart showing a third method of manufacturing a conventional nozzle substrate.

FIG. 11 is a process chart showing a fourth conventional method for manufacturing a nozzle substrate.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1; Ink jet printer, 2; Ink cartridge, 3; Recording head, 4; Carriage, 12; Nozzle substrate, 13; Diaphragm substrate, 14; Electrode substrate, 15; Nozzle, 16; , 20; individual electrodes,
21; first layer, 22; second layer, 23; nozzle hole, 24;
Nozzle communication hole, 25; ink supply groove, 30; master substrate, 31; circular pattern, 32; communication hole pattern, 3
3: supply groove pattern.

Continued on the front page F-term (reference) 2C057 AF78 AF80 AF93 AG04 AG07 AG08 AG14 AG30 AN01 AP02 AP13 AP25 AP28 AP38 AP60 AQ06 BA03 BA15

Claims (7)

[Claims] A nozzle substrate for forming a nozzle hole for discharging ink droplets in a first layer by electroforming a plurality of times, and a nozzle substrate having a nozzle communication hole communicating with the nozzle hole in the second and subsequent layers; A pressurized liquid chamber communicating with the nozzle is formed by the nozzle substrate and the vibrating plate substrate, and the vibrating plate is provided on one surface of the pressurized liquid chamber. In the recording head for discharging the ink from the nozzle, the nozzle communication hole of the nozzle substrate rises at an angle of 90 degrees or more from the first layer and is tapered with respect to the nozzle hole,
In addition, there is no gap at the interface between the nozzle hole and the inner peripheral surface of the nozzle communication hole of each layer forming the nozzle communication hole. 2. The method according to claim 1, wherein the first nozzle substrate has a nozzle hole.
The recording head according to claim 1, further comprising a water-repellent layer on at least the ink ejection surface side including the outer periphery of the nozzle hole. 3. A method of forming a nozzle hole for discharging ink droplets on a first layer by electroforming a plurality of times, and then forming a nozzle communication hole communicating with the nozzle hole on the second and subsequent layers, and vibrating with a nozzle substrate. A pressurized liquid chamber communicating with the nozzle is formed by the nozzle substrate and the vibrating plate substrate, and the vibrating plate is provided on one surface of the pressurized liquid chamber. Forming a nozzle communication hole of a nozzle substrate at an angle of 90 ° or more from the first layer and forming a tapered shape with respect to the nozzle hole, and communicating with the nozzle hole. A method for manufacturing a recording head, wherein a gap is formed at an interface between a nozzle hole of each layer forming a hole and an inner peripheral surface of the nozzle communication hole. 4. A nozzle hole in the first layer of the nozzle substrate, the opening end of which is formed on the side of the surface on which the second layer is formed, having a round shape.
4. The method according to claim 3, wherein the opening ends of the nozzle communication holes formed in the second and subsequent layers are formed in a round shape following the round shape of the opening ends of the nozzle holes. 5. The first layer of the nozzle substrate has a round-shaped opening at the opening end of the second-layer forming surface, and the opening end of the first layer has an inner peripheral surface of the round-shaped opening. 4. The method according to claim 3, wherein the second and subsequent layers are formed to form a nozzle communication hole having a round nozzle opening and an open end. 6. The method for manufacturing a recording head according to claim 3, wherein a water-repellent layer is formed on the ink ejection surface side including at least the outer periphery of the nozzle hole in the first layer in which the nozzle hole is formed. 7. An ink jet recording apparatus comprising a recording head produced by the production method according to claim 3.