JPH04164378A - Manufacture of laminated ceramic electrostrictive element - Google Patents

Abstract

PURPOSE:To perform electrophoresis to a laminated ceramic sintered body without forming any tentative electrode so that an electrolyte can be prevented front the contamination by the glass powder of the tentative electrode by using a jig for electrophoresis having electrode surfaces composed of numberless elastic recessing and projecting sections. CONSTITUTION:After a laminated ceramic sintered body 3 is set on a jig for electrophoresis having electrode surfaces composed of countless spring-like recessing and projecting sections, zinc passivation glass powder is electrodeposited on the sintered body 3 by dipping the sintered body 3 in an electrolyte 7 prepared by suspending the glass power in ethanol and connecting the sintered body 3 so that a positive voltage can be applied across the internal electrode side on which the glass powder is not electrodeposited. Then a glass insulating layer 14 is formed by baking the electrodeposited glass powder. After the insulating layer 14 is formed, an external electrode 15 is formed by printing conductive paste perpendicularly to the layer 14 and baking the past. Finally, laminated ceramic electrostrictive elements 16 are manufactured by slicing the laminated ceramic sintered body in the direction perpendicular to the insulating layer 14.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing a multilayer ceramic electrostrictive element, and particularly to a method for forming a glass insulating layer.

[Conventional technology]

Conventional laminated ceramic electrostrictive elements are made by laminating sheet-like piezoelectric ceramic members and internal electrode conductors alternately and pressurizing them at high temperatures, then firing the laminated body to create a laminated ceramic sintered body. Silver paste is applied to the exposed end face of every other electrode layer and baked to form a temporary electrode 20 as shown in FIG. This laminated ceramic 19 is
After setting it in an electrophoresis jig with electrode surfaces that make contact at two points as shown in the figure, the laminated ceramic sintered body is immersed in an alcoholic solution of iodine in which the glass powder shown in Figure 4 is dispersed. Glass powder is electrodeposited on the internal electrode every other layer on the end face where the internal electrode is exposed in its entirety, and baked to form an insulating layer, and electrodes are placed on each of the pair of side faces where the end face of the internal electrode conductor is exposed every other layer. It was manufactured by forming two comb-shaped electrodes by electrically connecting internal electrode conductors every other layer.

[Problem to be solved by the invention]

In the above-described conventional method for manufacturing a multilayer ceramic electrostrictive element, in the step of immersing a multilayer ceramic sintered body on which a temporary electrode has been formed into an electrolytic solution of glass powder to form a glass insulating layer, the temporary electrode is formed of glass powder. Since the solution leaks out into the electrolytic solution and contaminates it, the electrodeposition state of the glass and the insulation properties of the glass deteriorate, and there is a drawback that discharge failures are likely to occur in the glass layer portion of the multilayer ceramic electrostrictive element.

An object of the present invention is to prevent contamination of the electrolyte due to elution of temporary electrodes into the electrolyte when forming an insulating layer every other layer on the end face of an internal electrode conductor, improve the state of electrodeposition of glass powder, and improve the electrodeposition of the insulating layer. It is an object of the present invention to provide a method for manufacturing a multilayer ceramic electrostrictive element that has improved insulation properties, eliminates the formation of temporary electrodes, simplifies the process, and reduces the cost of the product.

[Means to solve the problem]

The method for manufacturing a laminated ceramic electrostrictive element of the present invention includes a step of forming a laminated ceramic sintered body in which sheet-shaped piezoelectric ceramic members and internal electrode conductors are alternately stacked, and a step of forming a laminated ceramic sintered body in which sheet-shaped piezoelectric ceramic members and internal electrode conductors are alternately stacked; a step of electrodepositing glass powder alternately on one end surface of the internal electrode conductor exposed on a pair of side surfaces, and baking the electrodeposited glass powder to insulate the end surface of the internal electrode every other layer on one end surface; A method for manufacturing a multilayer ceramic electrostrictive element, comprising: forming an insulating layer; and electrically connecting end surfaces of internal electrode conductors exposed on the pair of side surfaces to form two σ comb-shaped electrodes. , the electrodeposition of the glass powder is carried out by setting the laminated ceramic sintered body in an electrophoresis jig having an electrode surface with innumerable elastic uneven surfaces.

[Differences between the invention and the prior art]

As described above, after forming a temporary electrode for electrophoresis on a multilayer ceramic sintered body using the conventional manufacturing method for a multilayer ceramic electrostrictive element, it is set in an electrophoresis jig having an electrode surface that contacts at two points, and a glass powder is placed on the multilayer ceramic sintered body. In contrast, in the present invention, it is necessary to form temporary electrodes on the laminated ceramic sintered body by using an electrophoresis jig with countless elastic uneven surfaces on the electrode surface. The difference is that contamination of the electrolytic solution can be prevented when the glass powder is electrodeposited, and the electrodeposition state of the glass and the insulation properties of the glass are improved.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 2 is an exploded perspective view showing the laminated structure of a laminated body for explaining one embodiment of the present invention.

As shown in FIG. 2, a piezoelectric sheet 1 with a thickness of 135 μm
A piezoelectric sheet (1a) with internal electrode conductors 2 formed thereon was created by printing a conductive paste on one side of the surface, leaving a part of the band-shaped part, and nine piezoelectric sheets 1 on which no internal electrodes were formed. Piezoelectric sheet with internal electrodes placed on top) 1
a, and further arrange piezoelectric sheets with internal electrodes 1a so that the strip-shaped part on which no internal electrodes are formed is located on the opposite end surface, resulting in a total of 64 piezoelectric sheets with internal electrodes. 1a is laminated. Furthermore, ten piezoelectric sheets 1 are laminated thereon. The pressure of this laminate is 290 kg.
/cd for 9 hours and 70 minutes at a temperature of 110° C., and then sintered at a maximum holding temperature of 1120° C. and a holding time of 2 hours to produce a multilayer ceramic sintered body 3 as shown in FIG. After setting this laminated ceramic sintered body 3 in an electrophoresis jig having an electrode surface with numerous spring-like irregularities on the surface as shown in FIG. Glass powder is immersed in an electrolytic solution 7 of glass powder suspended in ethanol, and a DC power source 8 of 40 V is connected to apply a positive voltage to the internal electrode side that does not electrodeposit the glass powder.
, DC power source 9 is applied for 20V and electrodeposition is performed for 70 seconds.

The maximum holding temperature for electrodeposited glass powder is 620℃.

The glass insulating layer 14 is formed by baking for a holding time of 30 minutes as shown in FIG.

Next, a conductive paste is printed orthogonally to the glass insulating layer 14 and fired at a maximum holding temperature of 590°C and a holding time of 10 minutes to form external electrodes 15 and to form the multilayer ceramic sintered body 13.
Create.

Subsequently, as shown in FIG. 6, this laminated ceramic sintered body 13
in the direction perpendicular to the glass insulating layer 14 (XI
The multilayer ceramic electrostrictive element 16 is cut in the X2 direction).
Manufacture.

In order to compare the characteristics of the multilayer ceramic electrostrictive element 16 manufactured in this example with the characteristics of a conventional multilayer ceramic electrostrictive element, 100 multilayer ceramic electrostrictive elements having a shape of 2 x 3 x 10 mm and 64 internal electrode layers were fabricated. Quantity measurement and DC
A screening test was conducted in which 250V was applied for 30 minutes.

Table 1 shows the characteristics of this example in comparison with the conventional example.

As shown in Table 1, the amount of distortion when 150V was applied was 8.
5 μm, and has the same performance as the conventional example. Furthermore, in the screening test, the discharge defect occurrence rate in the glass insulating layer portion was 0%, and the quality of the glass insulating layer was improved compared to the conventional example.

Table 1 Next, Example 2 will be explained. This example differs from Example 1 in that an electrophoresis jig 18 (FIG. 7) having numerous needle-like electrode surfaces is used, and only this point will be described. As in Example 1, the laminated ceramic sintered body 3
(Fig. 2) is prepared.

After setting this laminated ceramic sintered body 3 in an electrophoresis jig 18 (Fig. 7) having numerous needle-shaped electrode surfaces, the zinc-based passivation glass powder shown in Fig. 4 was suspended in ethanol. The glass powder is immersed in an electrolytic solution 7, connected to apply a positive voltage to the internal electrode side on which the glass powder is not electrodeposited, and electrodeposited for 70 seconds by applying 40 V to the DC power source 8 and 20 V to the DC power source 9.

The maximum holding temperature for electrodeposited glass powder is 620℃.

The glass insulating layer 14 is formed as shown in FIG. 5 by baking under conditions of a holding time of 30 minutes to produce a multilayer ceramic electrostrictive element.

In order to compare the characteristics of the multilayer ceramic electrostrictive element manufactured in this example with the characteristics of a conventional multilayer ceramic electrostrictive element, 100 multilayer ceramic electrostrictive elements with a shape of 2 x 3 x 10 mm and 64 internal electrode layers were fabricated, and the amount of strain was measurement and DC25
A screening test was conducted in which 0V was applied for 30 minutes.

As a result, as shown in Table 2, the amount of distortion when 150V was applied was 8.5 μm, and the performance was equivalent to that of the conventional example. Furthermore, in the screening test, the discharge defect occurrence rate in the glass insulating layer portion was 0%, and the quality of the glass insulating layer was improved compared to the conventional example.

Table 2 [Effects of the Invention] As explained above, the present invention is capable of forming temporary electrodes on a laminated ceramic sintered body by using an electrophoresis jig having an electrode surface with countless elastic uneven surfaces. Since electrophoresis can be carried out without the need for electrophoresis, there is no contamination of the electrolytic solution of the glass powder by the temporary electrodes, which has the effect of improving the insulation properties of the glass insulating layer. Furthermore, for the same reason, there is no need for the process of applying and baking temporary electrodes, which has the effect of reducing costs.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an electrophoresis jig used in Example 1 of the present invention, and FIG. 2 is an exploded view showing the internal electrode conductor and laminated structure of an example of the method for manufacturing a multilayer ceramic electrostrictive element according to the present invention. 3 is a perspective view of a laminated ceramic sintered body in which the piezoelectric sheet 1 of FIG. 2 and the piezoelectric sheet 1a with internal electrode conductors are laminated, and FIG. 4 is a perspective view of the glass powder electrodeposition of the laminated ceramic sintered body. A schematic diagram of the process, FIG. 5 is a perspective view showing a state in which a glass insulating layer and an external electrode are formed on the multilayer ceramic sintered body of FIG. 2, and FIG. 6 is a diagram of a multilayer ceramic electrostrictive element manufactured according to the present invention. FIG. 7 is a perspective view of an electrophoresis jig used in Example 2 of the present invention, and FIG. 8 is a perspective view of a laminated ceramic sintered body on which temporary electrodes were formed in the contamination of manufacturing of a conventional laminated ceramic electrostrictive element. FIG. 9 is a perspective view of an electrophoresis jig used in the conventional manufacturing method. ■...Piezoelectric sheet, Ia...Piezoelectric sheet with internal electrode conductor, 2...Internal electrode conductor,
3,13゜19... Multilayer ceramic sintered body, 4
, 18.21... Electrophoresis jig, 5, 17.22
... Electrode surface, 6 ... Lead wire, 7 ...
...Glass powder electrolyte, 8,9...DC power supply, 10...Counter electrode, 11...Stirrer, 12...Magnetic Stirrer, 14... Glass insulating layer, 15... External electrode, 16... Multilayer ceramic piezoelectric element, 2
0...Temporary electrode. Agent Patent Attorney Susumu Uchihara Figure 5 Figure 7

Claims (1)

[Claims] A step of forming a multilayer ceramic sintered body in which sheet-like piezoelectric ceramic members and internal electrode conductors are stacked alternately, and one of the internal electrode conductors exposed on a pair of opposing sides of the formed sintered body, respectively. a step of electrodepositing glass powder alternately on the end faces of the electrode; a step of baking the electrodeposited glass powder to form an insulating layer that insulates the end faces of the internal electrodes every other layer on one end face; In the method for manufacturing a multilayer ceramic electrostrictive element, the method includes the step of electrically connecting the exposed end surfaces of the internal electrode conductors to form two comb-shaped electrodes, wherein the electrodeposition of the glass powder is applied to a surface of a countless elastic unevenness. 1. A method for manufacturing a multilayer ceramic electrostrictive element, the method comprising setting a multilayer ceramic sintered body in an electrophoresis jig having a flat electrode surface.