JPH08244220A - Ink jet recording head and manufacture thereof - Google Patents

Abstract

PURPOSE: To improve the printing quality and the yield and to reduce the cost by improving the accuracies of the size and the shape. CONSTITUTION: A board 1 is punched from a plastic sheet, and further an ink pressurizing chamber 4, an ink supply passage 5 and an ink reservoir 6 are punched as through holes. A filter channel 7 is formed as a fine channel of about several tens of μm by processing between the passage 5 and the reservoir 6 with an excimer laser. An ink nozzle 3 communicates with tip of the chamber 4. The board 1, a nozzle plate and a diaphragm are all punched from a polyetherimide sheet of crystalline thermoplastic resin material. The punched members have no warpage and no 'waviness', and high flatness. Of course, a correcting work for flattening after the punching is eliminated. In general, the yield is improved.

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 head which has high precision in size and shape and can improve printing quality, and at the same time, can reduce cost by improving yield rate and a manufacturing method thereof.

[0002]

2. Description of the Related Art A conventional example will be described with reference to FIG. 3 which is a plan view of a cavity plate thereof and FIG. 4 which is a sectional view thereof. Since the cavity plate 14 is easy to manufacture and can be mass-produced, a plastic molded product by injection molding is used, and the ink nozzle 3 having the axis in the thickness direction is penetrated through the cavity plate 14 and the upper surface thereof. Is a recess in which a plurality of sets (five sets in the figure) of the ejection passage 13, the ink pressurizing chamber 4, the ink supply passage 5, and the filter passage 7 connected to the ink nozzle 3 and a common ink reservoir 6 communicate with each other. Carved in the form of. The vibrating plate 8 is joined to the cavity plate 14 so as to cover the recess, and the outer surface of the vibrating plate 8 is
A piezoelectric element 10 as an electromechanical conversion element is joined via a common electrode 9 in correspondence with the position of the ink pressurizing chamber 4.
A drive electrode 11 is formed on the outer surface of the piezoelectric element 10, and a drive voltage for ink ejection is applied to the drive electrode 11 and the common electrode 9. The vibrating plate 8 vibrates in the direction perpendicular to the plane by the bimorph action based on the expansion and contraction movement of the piezoelectric element 10 due to the application of the drive voltage. This diaphragm 8
The vibration in the direction perpendicular to the surface of (1) sharply reduces the volume of the ink pressurizing chamber 4, ejects ink droplets from the ink nozzles 3 through the ejection passage 13 and prints on a recording paper (not shown).

[0003]

In the conventional example, the structure is simple, so that the size and weight can be reduced, the service life is semi-permanent, and the running cost is low, but on the other hand, there are many drawbacks as follows. There is. Since the cavity plate 14 is a plastic molded product obtained by injection molding, the ink nozzle 3, the ejection flow path 13, the ink supply path 5, and the like cause a dimensional change due to contraction after molding (a factor that deteriorates print quality).
The cavity plate 14 also causes warping and "waviness", and when it is connected to the diaphragm 8 in a related manner, an unbonded portion is likely to occur. Therefore, correction work for flattening at several hundreds of degrees Celsius after molding is required. There are factors such as a high yield rate and a high cost such as a die cost for injection molding.

The problem to be solved by the present invention is to solve the above-mentioned problems of the prior art, improve the accuracy of size and shape, improve the printing quality, and improve the yield rate. An object of the present invention is to provide an ink jet recording head that can reduce costs and a method of manufacturing the same.

[0005]

An ink jet recording head according to the present invention is provided with a flat plate-like substrate formed by connecting a through-hole-shaped ink reservoir and an ink pressurizing chamber via a through-groove-shaped ink supply passage. A flat nozzle plate having an ink nozzle communicating with an end of the ink pressurizing chamber and penetrating in the plate thickness direction; a vibrating plate; and a substrate composed of a nozzle plate and a vibrating plate on both sides thereof. It is configured to include an ink circulation structure that is laminated and joined in a sandwiched manner.

In the method of manufacturing an ink jet recording head according to the present invention, the substrate stores ink together with its outer shape,
The ink pressurizing chamber and the ink supply path are punched out from the plastic sheet, and after sandwiching the diaphragm from both sides of the vibrating plate and the nozzle plate before the ink nozzle is punched, the ink nozzle is attached to the nozzle plate of the ink pressurizing chamber. Holes are communicated with the end, or the substrate is filled with ink, the ink pressurization chamber and ink supply path are punched out from the plastic sheet, and the diaphragm and ink nozzle holes have been punched from both sides. The step of laminating and joining the nozzle plates of 1.

[0007]

In the ink jet recording head according to the present invention, the substrate has a flat plate shape, the ink reservoir, the ink pressurizing chamber and the ink supply path are formed as through holes, and the nozzle plate has a flat plate shape, and the ink nozzles are formed therein. Therefore, compared to conventional integrated plastic molded products, unlike dimensional accuracy and flatness due to shrinkage and deformation after molding,
Good dimensional accuracy and flatness are obtained, and the yield rate after stacking and joining is also improved.

Further, in the method of manufacturing an ink jet recording head according to the present invention, the substrate of the recording head, together with its outer shape, holds ink, the ink pressurizing chamber and the ink supply path are punched out from the plastic sheet, and are sandwiched from both sides thereof. After the vibration plate and the nozzle plate before drilling the ink nozzles are laminated and joined, the ink nozzle is communicated with the end of the ink pressurizing chamber to form a hole in the nozzle plate, or the nozzle plate with the ink nozzles already formed is laminated. Since they are joined together, they are easy to process, good dimensional accuracy and flatness are obtained, and the yield after stacking and joining is also improved.

[0009]

Embodiments of the ink jet recording head according to the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of the substrate of the embodiment, and FIG. 2 is a sectional view of the same. In these figures, a member corresponding to the cavity plate 14 in the conventional example is constituted by joining a flat plate-shaped substrate 1 and a nozzle plate 2 respectively. That is, the substrate 1
Is punched out from a plastic sheet, and the ink pressurizing chamber 4, the ink supply path 5 and the ink reservoir 6 are punched out as through holes. Here, the ink pressurizing chamber 4 has a slightly different shape from that of the conventional example, but since it is functionally the same, the same reference numeral as that of the conventional example is given for convenience. The filter flow path 7 is processed between the ink supply path 5 and the ink reservoir 6 by an excimer laser which is optimal for processing plastic,
It can be formed as a fine channel of about several tens of μm.
By the way, if the filter channel is designed as a groove having a relatively wide width, the ink pressurizing chamber 4 and the ink supply channel 5 are formed.
It is also possible to punch out at the same time as the ink reservoir 6. By the way, the minimum width that can be punched out is the thickness according to the experiment.
It was 0.2 mm for a 0.2 mm sheet and 0.1 mm for a 0.1 mm thick sheet.

The ink nozzle 3 communicates with the tip of the ink pressurizing chamber 4 in the embodiment, and once in the conventional example, once the ejection passage 1 is formed.
3 and communicates with the ink pressurizing chamber 4 via this. However, if the tip portion of the ink pressurizing chamber 4 of the embodiment is elongated and elongated to form the ejection passage 13 of the conventional example, the same is essentially the case. Alternatively, the ink nozzle 3 may be first processed into the nozzle plate 2 by an excimer laser and then bonded to the substrate 1 in a later process, or the nozzle plate in which the ink nozzle 3 is not processed first is used. 2 and the substrate 1 are joined together, and then the ink nozzle 3
May be processed. According to the latter process, troublesome alignment is not required when the substrate 1 and the nozzle plate 2 are joined, which is slightly convenient.

The substrate 1, the nozzle plate 2, and the vibrating plate 8
Both are punched from a sheet of polyetherimide, which is a crystalline thermoplastic resin material. The diaphragm 8 has a slightly different shape from that of the conventional example, but since it is functionally the same, the same reference numeral as that of the conventional example is given for convenience. Each punched member has good flatness without warping or "waviness". Of course, the correction work for flattening after punching is unnecessary. The bonding of each member was performed by solvent bonding using a solvent such as chloroform instead of thermocompression bonding due to the thermal deformation of the flow path, etc., and the yield rate was generally improved. A thermosetting adhesive was used to bond the vibration plate 8 and the piezoelectric element 10.

[0012]

According to the present invention, the following excellent effects can be expected. (1) Since the cavity plate is obtained by joining the flat plate substrate and the nozzle plate, the dimensional accuracy and flatness are impaired due to shrinkage and deformation after molding, compared to the conventional integral plastic molded product. Unlike the above, good dimensional accuracy and flatness can be obtained, and the yield rate after stacking and bonding is also improved. As a result, good print quality is obtained, manufacturing is facilitated, and cost can be reduced. (2) In particular, because the substrate is stamped from a plastic sheet, dimensional accuracy and flatness are good, while material costs are reduced due to effective use of materials.
Further cost reduction is supported.

[Brief description of drawings]

FIG. 1 is a plan view of a substrate according to an embodiment of the present invention.

FIG. 2 is a sectional view of an example.

FIG. 3 is a plan view of a conventional cavity plate.

FIG. 4 is a sectional view of a conventional example.

[Explanation of symbols]

 1 Substrate 2 Nozzle Plate 3 Ink Nozzle 4 Ink Pressurizing Chamber 5 Ink Supply Channel 6 Ink Reservoir 7 Filter Channel 8 Vibrating Plate 9 Common Electrode 10 Piezoelectric Element 11 Drive Electrode

Claims (3)

[Claims] 1. A flat plate-shaped substrate in which a through-hole-shaped ink reservoir and an ink pressurizing chamber communicate with each other through a through-groove-shaped ink supply passage; and an ink nozzle communicates with an end of the ink pressurizing chamber. And a vibrating plate; and an ink distribution structure in which the substrate is laminated and joined in such a manner that the nozzle plate and the vibrating plate are sandwiched from both sides thereof. An inkjet recording head, comprising: 2. The ink jet recording head substrate according to claim 1, wherein the outer shape of the ink reservoir, the ink pressurizing chamber and the ink supply path are punched out from a plastic sheet, and the diaphragm and the ink are sandwiched from both sides. A method for manufacturing an ink jet recording head, characterized in that after the nozzle is laminated and joined to the nozzle plate before being punched, the ink nozzle is bored in the nozzle plate so as to communicate with the end of the ink pressurizing chamber. 3. The substrate of the ink jet recording head according to claim 1, the ink reservoir, the ink pressurizing chamber and the ink supply path are punched out from a plastic sheet together with the outer shape thereof, and the diaphragm and the ink are sandwiched from both sides. A method for manufacturing an ink jet recording head, characterized in that a nozzle and a nozzle plate having holes are laminated and bonded.