JP2001225477A - Method for manufacturing ink-jet head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately and inexpensively manufacture in a short time a plurality of side walls for separating a plurality of ink chambers to have a high Young's modulus and a high thixotropy. SOLUTION: A mask material 25 with a plurality of mask parts 25 aligned to have a shape conforming to a shape of each ink chamber 20 is overlapped with a piezoelectric actuator 10. A liquid resin material which is to be the side wall 21 between ink chambers is filled between the plurality of mask parts 25a. Then the material is baked to be half set. The mask material 25 is removed with the side walls 21 left on the piezoelectric actuator 10. A substrate 30 is overlapped on the side walls 21, and the side walls are substantially baked to be of the high Young's modulus and the high thixotropy. The substrate 30 is a layer of a plurality of sheet-shaped materials with preliminarily formed nozzle holes and manifolds. The nozzle holes and manifolds are connected to ink chambers 20 when the substrate is overlapped on the side walls 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing an ink jet head.

[0002]

2. Description of the Related Art Conventionally, as a multi-nozzle type ink jet head, a plurality of ink chambers are formed with a wall separated by a side wall, and the ink filled in each ink chamber is selectively applied with an ejection energy by an energy generating means. There is a type in which ink droplets are ejected from nozzle holes provided corresponding to each ink chamber.

An ink jet head of this type requires a structure having an extremely fine ink chamber as the recording resolution increases. In the case of a resin material, such a fine structure can be molded by injection molding or the like. However, a resin material that is easy to mold has a too low Young's modulus and shrinks at the time of molding so that accuracy and flatness cannot be obtained. Although a method of injection-molding ceramics is also conceivable, there is a problem in that the shrinkage force differs depending on the location of the molded product, and accuracy cannot be obtained.
For this reason, usually, sintered ceramics or the like having a high Young's modulus are machined or etched to produce a metal.

[0004]

However, sintered ceramics are not only expensive but also difficult to machine.
When a plurality of ink chambers are formed, much processing time is required. Further, when metal is etched, there is a problem that the ink chamber is formed with a relatively large taper and accuracy is hardly obtained.

The present invention has been made in order to solve the above-mentioned problems, and provides a method of manufacturing an ink-jet head which can form a plurality of ink chambers in a short time and can be manufactured accurately and at low cost.

[0006]

According to a first aspect of the present invention, there is provided a method of manufacturing an ink jet head, comprising a plurality of ink chambers separated by side walls between two parallel plate members. A nozzle hole formed corresponding to each ink chamber by providing energy generating means corresponding to each ink chamber, and selectively applying ejection energy to the ink filled in each ink chamber by the energy generating means. In a method of manufacturing an ink jet head for ejecting ink droplets from,
Stacking a mask material in which a plurality of mask portions having a shape corresponding to the shape of each of the ink chambers are arranged on one of the two plate-like members; Filling the liquid material, curing the liquid material, removing the mask material while leaving the side wall on the one member after the material to be the side wall is cured, the one member And fixing the other of the two plate-like members on the side wall opposite to the above.

As described above, instead of injection molding, a plurality of ink chambers can be simultaneously formed by filling and curing a material in a mask material superimposed on one plate-like member and removing the mask material.
Also, it is formed with high accuracy.

Preferably, in the above manufacturing method, the step of curing the liquid material is a baking step, wherein the mask material is semi-cured before removing the mask material, and the other is cured. After the members are stacked, they are fully cured.
Accordingly, the high Young's modulus side wall is formed to increase the ink jetting efficiency, and the high Young's modulus side wall can be easily formed as described above.

Preferably, in the step of filling the liquid material, the material is filled between the plurality of mask portions by a blade moving while wiping the mask material. That is, the plurality of side walls are easily formed in a printing manner.

The present invention is suitable for a piezoelectric ink jet head. That is, as described in claim 4, the energy generating means is made of a piezoelectric material that is deformed by application of a voltage, and the one member is constituted by the piezoelectric material itself or a vibrating plate vibrated by the piezoelectric material. The material itself or the diaphragm is arranged over the plurality of ink chambers.

According to a fifth aspect of the present invention, the other member is a substrate having a plurality of nozzle holes corresponding to each of the ink chambers, thereby simplifying the shape of the ink chamber formed as described above. And facilitate molding.

Further, as described in claim 6, the substrate has a plurality of communication holes which communicate with a manifold for supplying ink to each of the ink chambers, so that the ink chamber formed as described above is formed. To make the shape of the
Makes molding easier.

According to a seventh aspect of the present invention, the substrate forming the other member is formed by laminating a plate-like material having the nozzle hole and the opening forming the manifold, thereby forming the nozzle hole and the manifold. make it easier.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are sectional views of an ink jet head manufactured by the manufacturing method of the present invention. This ink jet head includes a piezoelectric actuator 10 as an energy generating means, a layer including a plurality of side walls 21 forming an ink chamber 20 therebetween, and a piezoelectric actuator 1.
It is configured by laminating a substrate 30 that covers the open surface of the ink chamber 20 on the side opposite to 0.

The substrate 30 is formed by laminating a plurality of plate-like materials such as metal, glass, and ceramics by adhesion, solid layer diffusion, or, in the case of ceramics, a printing method.
The laminated structure has a nozzle hole 32 and a manifold 34.
Is provided. For example, as shown in the drawing, a plurality of rows of nozzle holes 32 are formed in the outermost plate-shaped material 31, and a manifold 34 is formed in the second and third plate-shaped materials 33. With an opening for The first plate-like material 31 and the fourth plate-like material 3 are positioned above and below the opening.
By forming the manifold 34, the manifold 34 that extends long in the direction parallel to the arrangement direction of the plurality of ink chambers 20 (in the direction perpendicular to the plane of FIG. 2) is formed. One end of the manifold 34 is connected to an ink supply source (not shown). The fourth plate-like material 35 is supplied from the manifold 34 to each ink chamber 20.
Has a communication hole 36 which communicates with one end. The second to fourth plate-like materials 33 and 35 corresponding to the other end of each ink chamber 20 have openings 37 communicating with the nozzle holes 32.

The piezoelectric actuator 10 includes a plurality of piezoelectric ceramic layers 11 stacked on each other, a plurality of internal positive electrode layers 12 between every other piezoelectric ceramic layer 11 so as to correspond to the position of the side wall 21, and the remaining one every other piezoelectric ceramic layer 11. A plurality of internal negative electrode layers 13 are formed between the piezoelectric ceramic layers corresponding to the ink chambers 20, respectively. The piezoelectric actuator 10 extends continuously over the plurality of ink chambers 20. The piezoelectric ceramic layer 11 is made of a lead zirconate titanate (PZT) -based ceramic material having ferroelectricity, and is polarized P in the laminating direction. The internal positive electrode layer 12 and the internal negative electrode layer 13 are formed by screen printing on a piezoelectric ceramic layer using an Ag-Pd-based metal material. A required number of sheets on which the internal positive electrode layer 12 or the internal negative electrode layer 13 is printed are laminated on a material for forming the piezoelectric ceramic layer 11, and a sheet having no internal electrode layer is stacked on top of the sheet, and the whole is heated. Press, degrease,
Sintering etc. The piezoelectric ceramic layer 11 thus obtained is manufactured by applying an electric field to perform a polarization process. In addition, a vibration plate that vibrates as the piezoelectric ceramic layer 11 is deformed can be interposed between the piezoelectric actuator 10 and the plurality of ink chambers 20.

When a voltage is selectively applied between the internal positive electrode layer 12 and the internal negative electrode layer 13 according to predetermined print data, the piezoelectric ceramic layer 11
An electric field E substantially in a direction perpendicular to the polarization direction P is generated, and the internal negative electrode layer 1
The portion corresponding to 3 is deformed in a direction to enlarge the ink chamber 20, and supplies ink from the manifold 34 to the ink chamber 20 through the communication hole 36. Thereafter, when the application of the voltage is stopped, the deformed piezoelectric ceramic layer is restored, pressure is applied to the ink in the ink chamber 20, and ink droplets are ejected from the nozzle holes 32 through the openings 37.

Hereinafter, a method of manufacturing the ink chamber 20 and the side wall 21 will be described with reference to FIG. As shown in FIG. 3A, a mask material 25 having a plurality of mask portions 25 a having a shape corresponding to the shape of the ink chamber 20 is prepared, and the mask material 25 is overlaid on the piezoelectric actuator 10. At this time,
The mask portion 25a is arranged so as to correspond to the internal negative electrode layer 13.

Then, as shown in FIG. 3B, one of the two blades 26 of the printing press is moved while wiping the mask material, and the liquid material 27 serving as the side wall is filled between the mask portions. . That is, the side wall is formed in a printing manner. As the material for forming the side wall, a resin having a high Young's modulus and a high thixotropy, preferably, a resin that is hardly deformed by an external force by containing a filler therein, for example, J8730X manufactured by DuPont or Chiba Nagase Made of T
693 / R1007TC-4 or the like can be used.

At this time, although the material 27 is filled so as to be pushed in by the blade 26, the unfilled portion S remains in the corner of the space between the mask portions 25a, so that the pressure before the material 27 is filled as described above is reduced. , Which is relatively lower than the subsequent pressure, and the pressure difference causes the material to fill to the corners. For example, the pressure before filling the material is 5 Torr, and the pressure after filling is 150
Torr. As a result, as shown in FIG. 3 (c), the other blade 26 is moved once again while wiping the mask material 25 to fill the sink marks formed on the surface of the material, that is, the concave portions R. The liquid material 27 is filled.

Thereafter, the material is fired to semi-harden the material for forming the side walls. For example, baking is performed at about 100 ° C. for about 1 hour. Then, by removing the mask material 25, FIG.
As shown in (d), the integrated side wall 21 is left on the piezoelectric actuator 10.

As shown in FIG. 3D, the substrate 3 is provided on the upper surface of the side wall 21 opposite to the piezoelectric actuator 10.
And fired at about 150 ° C. for about 1 to 2 hours.
Is fully cured, and the substrate 30 and the side wall 21 are integrated. The firing temperature is preferably a temperature at which the polarization of the piezoelectric actuator does not disappear. The substrate 30 includes a plurality of plate-like materials 3.
After laminating 1, 33, and 35, they may be overlapped on the side wall 21. Alternatively, after one plate-like material 35 is integrated with the side wall 21, another plate-like material 31, 33 can be laminated.

As described above, a high Young's modulus, high thixotropy resin material is filled between a plurality of mask portions, and the mask material is removed after semi-firing, whereby the side walls can be formed accurately without deformation or distortion during molding. be able to. Further, the side wall can be formed with almost no taper as compared with the case where it is formed by etching, and a plurality of side walls can be formed simultaneously and uniformly. Further, by firing the material, it is possible to increase the Young's modulus and thixotropy of the side wall and realize high-efficiency ink ejection with little energy loss. Further, since the nozzle holes and the communication holes communicating with the manifold are formed in the substrate 30 covering the plurality of ink chambers 20, the nozzle holes and the communication holes are formed at the ends of the ink chambers while reducing the width and depth thereof. Ink chamber 2
0 can be a single depth, so that it can be easily formed with a mask material of uniform thickness.

In the above-described embodiment, the energy generating means has a structure in which the piezoelectric ceramic layers 11 are laminated. However, the vibration element covering the plurality of ink chambers 21 is provided with a piezoelectric element or other element corresponding to each ink chamber. Various energy generating means can be used, such as a structure in which a vibration means is fixed, or a structure in which a heating element is arranged on a plate-like member covering a plurality of ink chambers 21 in correspondence with each ink chamber.

In the above embodiment, the side wall 21 is formed on the piezoelectric actuator 10.
The side wall 21 may be formed on 5. In this case, it is necessary to completely cover the communication hole 36 and the opening 37 with the mask material 25. Side wall 21 on piezoelectric actuator 10
Is not required, the positional accuracy of the mask material becomes relatively moderate.

[0026]

As is apparent from the above description,
In the manufacturing method according to the first aspect, instead of injection molding, a plurality of ink chambers are formed by stacking a mask material on one of the plate members, filling and curing the mask material, and removing the mask material. At the same time, it can be formed accurately with almost no taper.

Further, the side wall is baked and semi-cured, and after removing the mask material, a plate-like member covering the ink chamber is overlaid and fully cured, whereby the Young's modulus of the side wall is obtained. In addition, it is possible to enhance the thixotropic property and realize highly efficient ink ejection with little energy loss. Further, such a high Young's modulus and high thixotropy side wall can be easily formed as described above.

Preferably, the material is filled between the plurality of mask portions by a blade moving while wiping the mask material, so that a plurality of side walls can be printed easily and easily. It can be formed uniformly.

According to a fourth aspect of the present invention, in the piezoelectric type ink jet head, it is preferable to form the side wall on the piezoelectric material itself or on a vibration plate vibrated by the piezoelectric material as described above. it can.

Further, by providing a plurality of nozzle holes corresponding to each ink chamber on the substrate covering the ink chamber, the shape of the ink chamber formed as described above can be simplified. , Which can facilitate molding.

Further, as set forth in claim 6, the substrate is provided with a plurality of communication holes communicating with a manifold for supplying ink to each ink chamber, so that the ink chamber formed as described above is formed. The shape can be made simpler and the molding can be further facilitated.

According to a seventh aspect of the present invention, the substrate is formed by laminating a plate-shaped material having the nozzle hole and the opening forming the manifold, thereby facilitating the formation of the nozzle hole and the manifold. can do.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an inkjet head manufactured by a manufacturing method of the present invention, and is a cross-sectional view taken along line AA of FIG.

FIG. 2 is a sectional view taken along line BB of FIG.

FIG. 3 is a cross-sectional view of a manufacturing process illustrating a manufacturing method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Piezoelectric actuator (energy generation means) 20 Ink chamber 21 Side wall 25 Mask material 30 Substrate 32 Nozzle hole 34 Manifold 36 Communication hole

Claims (7)

[Claims] A plurality of ink chambers separated by side walls are formed between two parallel plate-like members, and energy generating means is provided in each of the ink chambers. In a method for manufacturing an ink jet head for selectively applying ejection energy by the energy generating means and ejecting ink droplets from nozzle holes provided for each ink chamber, a shape corresponding to the shape of each ink chamber is provided. A step of stacking a mask material having a plurality of mask portions arranged thereon on one of the two plate-like members; a step of filling a liquid material serving as the side wall between the plurality of mask portions; Curing the material of the above, after the material to be the side wall is cured, removing the mask material while leaving the side wall on the one member, on the side wall opposite to the one member, A method for manufacturing an ink jet head comprising a step of fixing overlapping the other member among the pieces of the plate-like member. 2. The method according to claim 1, wherein the step of curing the liquid material is a baking step, in which the mask material is semi-cured before removing the mask material, and after the other member is stacked,
A method for manufacturing an ink jet head to be fully cured. 3. The method according to claim 1, wherein the step of filling the liquid material comprises filling the material between the plurality of mask portions with a blade moving while wiping the mask material. 4. The piezoelectric device according to claim 1, wherein the energy generating means is made of a piezoelectric material that is deformed by applying a voltage, and the one member is constituted by the piezoelectric material itself or a vibration plate vibrated by the piezoelectric material. A method for manufacturing an ink jet head, wherein a material itself or a vibration plate is arranged over the plurality of ink chambers. 5. The method according to claim 1, wherein the other member is
A method of manufacturing an ink jet head which is a substrate having a plurality of nozzle holes corresponding to each of the ink chambers. 6. The method according to claim 5, wherein the substrate has a plurality of communication holes communicating with a manifold for supplying ink to each of the ink chambers. 7. The method according to claim 6, wherein the substrate constituting the other member is formed by laminating a plate-like material having the nozzle hole and the opening constituting the manifold.