JPS6050359B2 - Method for manufacturing piezoelectric material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a piezoelectric material, particularly a lead-based piezoelectric material, and particularly to a method for producing a piezoelectric material that has good peelability and a smooth surface when laminated and fired. There is one aimed at obtaining a piezoelectric sheet.

Recently, piezoelectric ceramics have been applied to a wide variety of fields, and their density and size have rapidly increased.

Conventionally, piezoelectric elements in a predetermined shape were obtained by cutting and polishing a sintered or single-crystal ingot depending on the application, but this resulted in deterioration of electrical characteristics due to processing distortion and increased processing costs. A problem has arisen. for that,
From the standpoint of process simplification and mass production, it is desirable to be able to supply elements in desired shapes at low cost simultaneously with firing.
In this method, a ceramic material is kneaded with a binder resin, etc., molded to produce a certain green sheet, punched into a predetermined shape according to the application, and then a high melting point oxide is uniformly applied to it and laminated and fired. It is known. However, in sintered sheet products after lamination firing, the yield decreases due to fusion between the sintered sheet and the high melting point oxide, adhesion between the sintered sheets, etc. Problems included sheet cracking, bleeding of silver electrodes, and a significant impact on electrical characteristics after assembly. The present invention provides a method for manufacturing a piezoelectric material that eliminates such problems. That is, in order to obtain a piezoelectric sintered sheet that is smooth, has good releasability, and is stable when piezoelectric materials are laminated and fired, zirconium oxide is heat-treated in the range of 1000 to 1600°C in advance. The particle size distribution is 28 to 140 μm. Generally, commercially available zirconium oxide products are often used as a single composition such as ceramics, and therefore are highly reactive materials. Therefore, it is fused to the sintered body sheet during firing. Therefore, it is preferable to heat-treat zirconium oxide in advance at as high a temperature as possible to lower its reactivity. When the treatment temperature is lower than 1000°C, reactivity remains, so the piezoelectric sheet and zirconium oxide are fused together. Moreover, when the temperature is higher than 16000C, the zirconium oxide particles react with each other, and the particle size becomes too large, resulting in poor releasability. From such a thing,
The heat treatment temperature is suitably in the range of 1000 to 1600'C. Next, regarding the particle size of the heat-treated zirconium oxide, when the particle size is larger than 140 pm, the contact area between the green sheet and zirconium oxide becomes smaller and it becomes difficult to adhere to the raw sheet. The contact area becomes large, making it difficult to peel off after firing, making it easy to break when peeling off the sintered sheet, and even if it can be peeled off, the sintered sheet will have poor smoothness.
A particle size distribution range of 28 to 140 μm is suitable. The zirconium oxide powder selected in this way is attached to the surface of a randomly punched piezoelectric sheet by applying heating vibrations, stacked and fired, resulting in a piezoelectric sintered body that is smooth and has stable peelability. You can get a seat. Next, in order to clarify the effects of the present invention, examples will be explained.

[Example 1] PbTiO3:PbTrZ3:Pb with a particle size of 0.5 μm
(Mgll3Nb2ノ3)03=37.5:25.0:
Pb (Mg, Nb, Tj, Zr) with a composition ratio of 37.5
) 03 series calcined raw material, 1.5% by weight of polyvinyl butyral resin, 0.5% by weight of dibutyl phthalate and 0.03% by weight of polyvinyl butyral resin.
Dioctyl phthalate was added in an amount of 5% by weight, and methyl alcohol in an amount of % by weight of silver and butyl alcohol in an amount of 5% by weight were further added to the calcined raw materials, and mixed in a ball mill for an hour to prepare a slurry.

This slurry was poured onto a polyester film, formed into a sheet by a doctor blade method, and then force-dried at 40'C to produce a green sheet. Next, it was punched out into a disk shape with a diameter of 3 mm using a punching machine. Inside the parts feeder (hereinafter referred to as parts feeder) that has a vibration mechanism,
Zirconium oxides having different particle sizes and heat treatment temperatures shown in the table below were heated to 60° C., allowed to flow for 5 minutes, and adhered to the surface of the raw sheet. Then, after stacking it in 8 layers, 13
It was fired at 00°C. The peelability and smoothness of the obtained piezoelectric sintered sheet are shown in the table below. 1000-16 like this
Even if heat treated at 00℃ and laminated with zirconium oxide with a particle size distribution of 28 to 1401 J, m,
It was possible to obtain a sintered sheet that has excellent smoothness and can be peeled off stably.

As explained above, the method of the present invention heat-treats zirconium oxide in advance to reduce its reactivity,
Furthermore, by limiting the particle size distribution, it is possible to produce a piezoelectric material with excellent release properties and properties.

Claims (1)

[Claims] 1 Add a binder resin, a plasticizer, and a solvent to a piezoelectric material containing lead, knead it, spread the kneaded product to a certain thickness to make a green sheet, and punch it into a predetermined shape.
A method for manufacturing a piezoelectric material, which comprises: adhering zirconium oxide having a particle size of 28 to 140 μm heat-treated at 000 to 1600° C. to the surface of a raw sheet, stacking a plurality of the raw sheets and firing the raw sheets.