JPH055830U - Piezoceramics firing sheet - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention relates to a firing sheet used for firing piezoelectric ceramics. [Structure] A baking sheet a in which a composition comprising a boron nitride powder 3, a dispersant and a binder is provided on both surfaces of a stabilized zirconia sheet 1 as a baking sheet.
Is.

Description

[Detailed description of the device]

[0001]

[The purpose of the device]

[0002]

[Industrial application]

 The present invention relates to a firing sheet used when firing a piezoelectric ceramic.

[0003]

[Prior Art]

When firing a piezoelectric ceramic made of PdO, ZrO ₂ and Ti, (1) stack the firing body in an airtight sheath, and spray zirconia powder as a release agent on each to fire or process, (2) If the thickness of the firing body is 1 mm or less, a sheet for firing piezoelectric ceramics, in which a sheet made of pulp paper is coated with alumina powder, carbon powder, a dispersant, and a binder on both sides. Are using.

[0004]

[Problems to be solved by the device]

 When piezoelectric ceramics are laminated and fired, the method shown in (1) above causes variations in the thickness of the fired body due to the zirconia powder to be spread, and the method shown in (2) causes the alumina powder applied to the sheet surface. However, since it is very close to the melting point of the particles of the firing body, a reaction occurs and the fired body is apt to fuse.

The conventional technique having the above problems is disclosed in the application of piezoelectric ceramics (published by Gakudonsha, edited by New Ceramics Editing Committee, P29-30, 1989.11.6). Therefore, the present invention has its technical problem to provide a firing sheet that does not cause fusion between piezoelectric ceramics when laminating ceramic products having a shape such as a disc or a square plate and firing them. is there.

The technical measures taken to solve the problems are as follows.

As a piezoelectric ceramic firing sheet used when firing piezoelectric ceramics by laminating them, a composition comprising a powder of boron nitride, a dispersant and a binder is coated on both sides of a stabilized zirconia sheet.

[0008]

[Action]

 Since the firing base of the piezoelectric ceramic and the boron nitride contained in the coating agent have different melting points, fusion of the fired body is prevented, and the occurrence thereof is small.

[0009]

【Example】

 The implementation will be described below.

A coating layer having a composition of boron nitride, a dispersant, and a binder is spray-coated on both surfaces of a 1 mm-thick stabilized zirconia sheet to a thickness of 40 to 60 μm on both sides and dried.

FIG. 1 is an enlarged cross-sectional view of a firing sheet, 1 is a stabilized ZrO ₂ sheet, 2 is a coating layer, and 3 is a boron nitride powder.

The sheet a thus formed is placed between the laminated piezoelectric ceramics (A, B, C, ...) Which is a molded body of a disc having a thickness of 2.5 mm, and the sheets are laminated to provide airtightness. It is put in a pod 4 and fired, which is shown in FIG.

As a mass-production method, a piezoelectric ceramic molded body obtained by automatic pressing is degreased and placed in an alumina sheath for firing. In this case, the molded bodies are laminated and fired, and the sheet a is laid between the molded bodies.

Next, in Table 1, a comparison of two data of the present invention (referred to as Examples 1 and 2) and a conventional example is described with respect to composition and waviness of a baked product.

[0015]

[Table 1]

From Table 1, in Examples 1 and 2, the dimensional change such as waviness is about 1/10 or less as compared with the conventional example.

[0017]

[Effect of the device]

The present invention has the following effects. That is, although only the stabilized zirconia sheet may be used, this firing method can prevent waviness and the like, but ZrO ₂ contained in the sheet reacts with ZrO ₂ contained in the fired body. Although the composition may be different, in the case of the present invention, since the melting point of the firing base and the boron nitride contained in the coating agent are different, it prevents fusion (reaction prevention), and also the release type of the sheet is good. No coating powder adheres to the body.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an embodiment.

FIG. 2 is an explanatory view using a firing sheet.

[Explanation of symbols]

 1 Stabilized zirconia sheet 2 Coating layer 3 Boron nitride powder

Claims (1)

[Claims for utility model registration] [Claim 1] When the piezoelectric ceramics are laminated and fired, as a piezoelectric ceramics firing sheet that is placed between the firing bodies and fired, both sides of the stabilized zirconia sheet are nitrided. A sheet for firing a piezoelectric ceramic, which is obtained by coating a composition including a powder of boron, a dispersant, and a binder.