JPH05229129A - Production of piezoelectric element for ink jet print head - Google Patents

Abstract

PURPOSE:To propose a method for producing a low-cost and high-reliability ink jet printer head piezoelectric element so structured as to have a plurality of ink grooves, walls of a piezoelectric material, and drive electrodes disposed on the both side surfaces of the ink grooves for applying an electric field to the piezoelectric material. CONSTITUTION:A production method is composed of a process for two sorts of green sheets 11 (32) and 21 as a piezoelectric material are alternately laminated by the number corresponding to the number of ink grooves; a process for thermally contact bonding a laminate body 31; a process for forming the thermally contact-bonded body as an integral body by sintering; and a process for cutting the sintered body at a surface in parallel to a laminating direction as well as in parallel to a longitudinal direction of a part forming the ink grooves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a piezoelectric element for an ink jet printer head, and more particularly, it has a plurality of ink grooves and a partition wall of piezoelectric material, and an electric field is applied to the piezoelectric material. The present invention relates to a method for manufacturing a piezoelectric element for an inkjet printer head having a structure in which drive electrodes for doing so are arranged on both sides of each ink groove.

[0002]

2. Description of the Related Art Conventionally, as one of non-impact printer heads, a piezoelectric ink jet printer head has been proposed which utilizes the electromechanical conversion function of a piezoelectric element for ejecting ink. As a printer head using this type of piezoelectric element, for example, Japanese Patent Application Laid-Open No. 63-247051 describes a printer head that uses shear deformation of a piezoelectric material for ejecting ink. This printer head includes a nozzle plate having a large number of ink ejection holes, a piezoelectric element made of a piezoelectric material having a large number of ink grooves and driving electrodes formed on the side surfaces, to which the nozzle plate is connected, and ink replenishment. And a liquid supply mechanism of. In the printer head, when an electric field is applied to the drive electrode, the wall of the piezoelectric material undergoes shear deformation, causing a change in volume of the ink groove.
As a result, the liquid pressure in the ink groove changes, and ink is ejected from the ejection holes of the nozzle plate.

As a method of manufacturing a piezoelectric element having a plurality of ink grooves, a method is proposed in which the piezoelectric material bonded to the substrate or the piezoelectric material itself is processed with an ink groove using a diamond cutter blade, a laser or the like. Has been done. When such a piezoelectric element is applied to an inkjet printer head, it is necessary to form a large number of ink grooves with high accuracy in order to improve the degree of integration of ink ejection holes. Further, in order to effectively utilize the shear deformation of the piezoelectric material, it is necessary to increase the height dimension with respect to the width dimension of the wall of the piezoelectric material.

[0004]

However, in the method of processing the ink groove using the above-mentioned diamond cutter blade or laser, it is necessary to form a large number of deep ink grooves effective for shear deformation of the piezoelectric material. In that case, the manufacturing method was extremely inefficient and the manufacturing cost was high. Also, because it is machined,
There were many problems in terms of reliability, such as the occurrence of microcracks in the piezoelectric material. The present invention has been made in order to solve the above-mentioned problems, and has a high degree of integration of ink grooves, and a piezoelectric element for an inkjet printer head that can effectively utilize shear deformation of a piezoelectric material for ejecting ink liquid,
It is intended to provide a method that can be manufactured at low cost.

[0005]

In order to achieve this object, a method of manufacturing a piezoelectric element for an ink jet printer head according to the present invention has a plurality of ink grooves and partition walls of a piezoelectric material which are alternately arranged. In the method for manufacturing a piezoelectric element for an ink jet printer head having a structure in which a drive electrode for applying an electric field to each of the ink grooves is provided with a through hole having a small diameter for degassing during sintering. Then, a first piezoelectric material green sheet for forming a partition wall of the piezoelectric material and a second piezoelectric material green sheet having a penetrating portion for forming the ink groove are provided as a second piezoelectric material green sheet. The steps of alternately stacking the sheets until the number of ink grooves corresponds to the number of ink grooves, forming a laminate, thermocompression-bonding the laminate to form a thermocompression-bonding body, and sintering the thermocompression-bonding body. do it Embody has the steps of forming a sintered body, and cutting by a plane parallel to the longitudinal direction of the through portion constituting and ink channels parallel to the stacking direction of the sintered body.

[0006]

According to the method of manufacturing a piezoelectric element for a printer head of the present invention having the above-mentioned structure, the first and second types of piezoelectric material green sheets are used, and the number of ink grooves required for the second green sheet is the same. After alternately stacking (for example, n pieces), the stacked body is thermocompression-bonded, and the thermoplasticity of the organic component contained in the green sheets is utilized to bring the stacked green sheets into close contact with each other. The thermocompression bonded body is completely integrated by sintering it according to the sintering conditions of the piezoelectric material used. Then, during the sintering process, a small-diameter through hole provided in the first green sheet for venting gas and a through-hole provided in the second green sheet for forming an ink groove are formed. , Acts as a passage for the gas generated by the decomposition of the organic component, and a good sintered body without cracks can be obtained. Finally, by cutting this sintered body along a plane parallel to the stacking direction and parallel to the longitudinal direction of the penetrating portion forming the ink groove,
A piezoelectric element for an ink jet printer head having n ink grooves and (n-1) piezoelectric material partition walls is manufactured.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the manufacturing method of the present invention will be described below with reference to the drawings.

In this example, lead zirconate titanate-based piezoelectric ceramics were used as the piezoelectric material. Average particle size 0.
To 5 μm lead zirconate titanate ceramic powder, polyvinyl butyral as a binder, polyethylene glycol as a plasticizer, octyl phthalate, and menhaden oil as a deflocculant were added in appropriate amounts, and a mixed solution of trichlorethylene and ethyl alcohol was added. As a solvent, the mixture was uniformly mixed in a ball mill for 24 hours to prepare mud.

[0009] Using the sludge prepared as described above,
Thickness after drying by doctor blade method is 0.11mm
Was molded into a green sheet. After the green sheet was dried, it was processed into two types of green sheets by punching.

First, as shown in FIG. 1, the first green sheet 11 has three small-diameter through holes 12 formed at one side thereof at equal intervals. The outer dimensions of the green sheet 11 are 25
× 18 mm, the thickness was 0.11 mm, and the diameter of each through hole 12 was 1 mm.

As shown in FIG. 2, the second green sheet 21 has three penetrating portions 22 for forming ink grooves.
Are opened in parallel along the width direction. The external dimensions of the green sheet 21 are 25 × 18 mm, the thickness is 0.11 mm, and the size of the penetrating part 22 is 20 × 2.25.
mm.

FIG. 3 is a perspective view showing an outline of a laminated body 31 in which two kinds of green sheets 11 and 21 are alternately laminated and thermocompression bonded. As shown in the figure, in this embodiment, nine first green sheets 11 are alternately laminated so as to be sandwiched by the second green sheets 21, and the uppermost surface and the lowermost surface have the same structure as the green sheet 11 described above. Then, a thick green sheet 32 having a thickness of 0.5 mm was laminated. Then, this laminated body was thermocompression-bonded to be adhered so that there was no gap between the layers of the green sheets 11, 21, and 32.

FIG. 4 is a perspective view schematically showing a sintered body 41 obtained by integrally sintering the laminated body 31 and a cutting processing direction thereof.
The laminated body 31 thermocompression-bonded as described above is put into a sintering furnace, slowly heated to 500 ° C., and held, so that the organic components contained in the green sheets 11, 21, and 32. Are oxidized, pyrolyzed and removed. After that, with the temperature further raised to 1300 ° C.,
By holding for about 1 hour, a high density sintered body 41 as shown in FIG. 4 is obtained.

By cutting the sintered body 41 by a plane parallel to the stacking direction and parallel to the longitudinal direction of the penetrating portion 22 forming the ink groove, as shown by the dotted arrow in FIG. A piezoelectric ceramic plate 51 having individual ink grooves was formed.

FIG. 5 is a perspective view schematically showing the piezoelectric ceramic plate 51. The operation of cutting the sintered ceramic body 41 into the piezoelectric ceramics plate 51 for processing was performed by a cutting machine using a diamond cutter blade having a thickness of 1 mm.
The external dimensions of the piezoelectric ceramic plate 51 obtained at this time were 2.5 × 20 mm and the thickness was 1 mm. In addition, each of the ten ink grooves 6 formed on the piezoelectric ceramic plate 51
2 is width 0.085mm, depth 0.35mm, length 16m
At m, each partition wall 63 made of nine piezoelectric ceramic materials between the ink grooves 62 has a width of 0.085 mm and a height of 0.3.
The length was 5 mm and the length was 16 mm.

Next, the piezoelectric ceramic plate 51 is dipped in silicon oil, and a direct current electric field of 3 kV / mm is applied for 15 minutes in the thickness direction using a flexible electrode at a temperature of 80 ° C. to perform polarization treatment. It was Then, the ink groove 62
An electrode was formed on the side surface of the substrate using a dry process such as vacuum deposition or sputtering. Then, after removing unnecessary electrode portions, both ends of the piezoelectric ceramic plate 51 were cut to obtain a piezoelectric element 61. FIG. 6 is a perspective view showing an outline of the piezoelectric element 61.

FIG. 7 is an exploded perspective view showing an ink jet printer head recording section 71 using the piezoelectric element 61 of this embodiment. The piezoelectric element 61 has ten ink grooves 62 and 9
A piezoelectric ceramic material partition wall 63 is provided, a drive electrode (not shown) is formed on the side surface of the ink groove 62, and an ink introduction port 73 is provided on one side of the upper surface of the piezoelectric element 61. The cover plate 72 is adhered. After that, the nozzle plate 74 having the ink ejection holes 75 corresponding to the ink grooves 62 is bonded to one end surface of the piezoelectric element 61. Further, on the drive electrodes formed on the side surfaces of each ink groove 62,
A driver circuit (not shown) is connected to form an inkjet printer head recording unit 71.

Next, the ink jetting operation of the ink jet printer head 71 of the above embodiment will be briefly described. When a voltage is applied to the drive electrode formed on the side surface of the ink groove 62, an electric field is applied to the partition wall 63 of the piezoelectric ceramic material in the direction orthogonal to the polarization direction.
At this time, shear strain is generated in the partition wall 63 made of the piezoelectric ceramic material. The direction of this shear strain is determined by the direction of the applied electric field. Therefore, the partition walls 63 made of the piezoelectric ceramic material on both sides of the arbitrary ink groove 62 that ejects the ink liquid are first deformed in the direction in which the volume of the ink groove 62 increases. After that, the electric field is instantly removed to restore the partition wall 63 of the piezoelectric ceramic to the original state. At this time, a pressure wave is generated as the volume of the ink groove 62 decreases, and the ink liquid pressure changes. The ink groove 62 is
It functions as an ink flow path and a pressure chamber, and ink liquid is ejected from an ink ejection hole 75 provided on the front surface of the ink groove 62.

The manufacturing process according to the present invention described above is
This is a very low cost and highly reliable construction method because the manufacturing process and the manufacturing apparatus that have been conventionally used for a laminated ceramic capacitor or a laminated piezoelectric actuator can be used.

[0020]

As is apparent from the above description, according to the method of manufacturing a piezoelectric element of the present invention, it has a plurality of ink grooves and a partition wall of piezoelectric material, and an electric field is applied to the piezoelectric material. A piezoelectric element for an inkjet printer head having a structure in which drive electrodes for the ink grooves are arranged on both side surfaces of the ink groove can be efficiently and reliably manufactured, the manufacturing cost is easy, and the quality is good. is there.

[Brief description of drawings]

FIG. 1 is a perspective view schematically showing a first green sheet used in a manufacturing method of the present invention.

FIG. 2 is a perspective view schematically showing a second green sheet used in the manufacturing method of the present invention.

FIG. 3 is a perspective view schematically showing a laminated body in which two types of green sheets are alternately laminated and thermocompression bonded.

FIG. 4 is a perspective view schematically showing a sintered body obtained by integrally sintering a laminated body and a cutting processing direction thereof.

FIG. 5 is a perspective view schematically showing a piezoelectric ceramic plate.

FIG. 6 is a perspective view schematically showing a piezoelectric element.

FIG. 7 is an exploded perspective view showing an inkjet printer head recording unit.

[Explanation of symbols]

 11 Green Sheet 12 Through Hole 21 Green Sheet 22 Through Portion 31 Laminated Body 41 Sintered Body 61 Piezoelectric Element 62 Ink Groove 63 Partition Wall

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takahiro Kanegae 15-1 Naesehiro-cho, Mizuho-ku, Nagoya-shi Brother Industrial Co., Ltd. Within

Claims (1)

[Claims] 1. An ink jet having a structure in which a plurality of ink grooves and partition walls of a piezoelectric material are alternately arranged, and drive electrodes for applying an electric field to the piezoelectric material are arranged on both side surfaces of each ink groove. In a method for manufacturing a piezoelectric element for a printer head, a first piezoelectric material green sheet for forming a partition wall of the piezoelectric material, which has a small diameter through hole for venting gas during sintering, and the ink groove. And a second piezoelectric material green sheet having a penetrating portion for forming a layer, the second piezoelectric material green sheet being alternately laminated until the number of second piezoelectric material green sheets corresponds to the number of ink grooves, thereby forming a laminate. A step of thermocompression-bonding the laminated body to form a thermocompression-bonded body; a step of sintering and integrating the thermocompression-bonded body to form a sintered body; Length of the penetrating part that constitutes the ink groove Method for manufacturing a piezoelectric element for an ink jet printer head, characterized by a step of cutting by a plane parallel to the direction.