JPS58131727A - Method of producing laminated porcelain capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a multilayer ceramic capacitor used as an electronic component.

In the production of multilayer ceramic capacitors.

On a raw ceramic sheet containing dielectric material.

Multiple sheets with internal electrodes printed on them are all laminated and pressed together. This internal electrode printing part consists of an effective internal electrode part and an external electrode extraction part connected to it, and is printed on the green sheet with a paste containing a conductive material. In this case, is the width of the external electrode extraction part simply the same width as the effective internal electrode part?
It is printed with a slightly smaller width. All sheets printed in this way are stacked and cut so that the external electrode extraction parts are alternate.9 For example, if the number of sheets stacked is 40 or more, the external electrode extraction parts will overlap on each side by 20 or more sheets. . Since the external electrode extraction portion is more difficult to cut than the raw ceramic sheet, it is subjected to cutting stress in the subsequent cutting process, and cracks occur in the vicinity of the effective internal electrodes in parallel to the cut surface. If the raw ceramic sheet is relatively thick, the cutting stress can be absorbed by the raw ceramic sheet, but if the thickness of the raw ceramic sheet (internal electrode spacing) is 20~
The thinner it is within 100μm, and the larger the number of laminated sheets (,), the better (
n≧40) Cracks are likely to occur. The cracks occur continuously over several layers or tens of layers, significantly reducing the reliability of the multilayer ceramic capacitor.

The present invention aims to eliminate such drawbacks.

When forming the internal electrodes on the raw sheet, the shape is deformed so that the cut surface side becomes narrower between the external electrode part electrode and the cutting position in the cutting process. The cutting stress is completely reduced, and the stress is concentrated near the cutting surface, thereby extremely reducing the frequency of cracks that occur near the effective internal electrode and parallel to the cutting surface.

A highly reliable multilayer ceramic capacitor can be obtained.

Hereinafter, nine embodiments of the present invention shown in the drawings will be described in detail.

As a ceramic material, Pb ((Nb 1/2.
Fe 1/2) 0.67 (W J/3, p@2
A composite peropskite dielectric material having a composition of 7'5) 0.33] Os f was used.

This material was mixed, pre-baked, and ball-milled, then dispersed in ethylceron lube to create a slurry mixed with PVB and BPBG, and then a 60 μm thick green sheet was created on a polyester film using a doctor plaid. As shown in FIG. 1, this green sheet 1 was printed using a screen printing method.

The internal electrodes 2 in the illustrated pattern were printed.

The internal electrode 2 was provided along one side of the effective internal electrode section 21 by dividing the external lead-out electrode section 22 into a plurality (n).

The number of sheets printed was 61, and the internal electrodes used were made by kneading noble metal powders Ag and Pd powders with a binder. The printed sheet was peeled from the polyester film, punched out into a shape with a predetermined size (120 x 100 m), laminated, and pressure-bonded. This laminate was placed on a plate heated to 90"C for 02
■Cut into raw chips of specified size using a thick cutter.

After cutting, deburring IJ, and firing at 900° C., the multilayer ceramic capacitor was evaluated for electrode characteristics and life test.

The results are shown in the table below. Table 1 also shows the evaluation results of capacitors using the conventional method. 'Also. Dimensions a of each part shown in FIG.

b, X7. The results of two Examples 1 and 2 with different X2 are shown. Incidentally, the outline of the appearance of the end portion of the manufactured capacitor is shown in Fig. 2. Figure 2 (a), (b), (
e) are the conventional method and Example 1 in Table 2, respectively. This corresponds to the second embodiment.

[Brief explanation of drawings]

FIG. 1 is a plan view of a raw sheet having nine internal electrodes according to an embodiment of the present invention, and FIG. 2 is a schematic end view of the manufactured capacitor, and (a), (b), and (e) are respectively Conventional example, Example 1. This corresponds to Example 2. DESCRIPTION OF SYMBOLS 1... raw sheet, 2... internal electrode, 21... effective internal electrode part, 22... external extraction electrode part.

Claims (1)

[Claims] 1. On a raw ceramic sheet containing dielectric powder. In a method of manufacturing a laminated ceramic capacitor by printing paste paste containing a conductive material for internal electrodes into a predetermined shape, laminating, crimping, cutting, and firing a plurality of sheets, the paste for internal electrodes is applied onto the raw sheet. In the printing process, the external electrode extraction part provided continuously on one side of the effective internal electrode part is divided into a plurality of parts along the negative side thereof, and the width in the cutting direction in the cutting process of each of the divided parts is A method for manufacturing a multilayer capacitor characterized by printing a shape that becomes thinner at the cutting position. Remaining days below