JPS6290905A - Manufacture of voltage nonlinear resistance element - 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 A. Field of Industrial Application The present invention relates to a method for manufacturing a voltage nonlinear resistor element containing zinc oxide as a main component.

B. Summary of the Invention The present invention involves adding a dispersant to raw material powder when manufacturing a voltage nonlinear resistor element containing zinc oxide as a main component.
e as octylamine acetate (C8H,,NH,・CH
, 000) is used for wet mixing to lower the viscosity of the resulting slurry and uniformly mix the raw material powders.

C. Conventional technology A voltage nonlinear resistor element containing zinc oxide as a main component consists of zinc oxide (znO) 1:bismuth oxide (Bi) as an additive component.
2O2), cobalt oxide (COwes), antimony oxide (5btOs), manganese dioxide (MnOt),
Chromium oxide A (Cr, O,), silicon dioxide (SiO7)
, nickel oxide (NiO), boron oxide (Btus), etc., are mixed using an emulsifier (disper mill) or a ball mill mixing device to form a slurry L.
A granulated powder is produced from this slurry, molded and fired.

D Problems to be Solved by the Invention Silicon dioxide (Sin,), chromium oxide (Or, O, ), and fluorine oxide (B, 03) in the above raw material powder have a gelling-promoting effect, so the mixing operation is difficult. When the slurry has a high viscosity and high thixotropic properties, it tends to gel, making uniform mixing difficult. Therefore, polyvinyl alcohol (PVA) is usually used. However, it is not sufficiently effective. As a result, stable granulated powder cannot be obtained in the next step. In the case of press molding with a mold, the molding density of the elements manufactured from 10 pieces varies, resulting in a deterioration in the quality of the voltage nonlinear resistor element containing zinc oxide as a main component.

E. Means for Solving the Problems The present invention has been made to solve the above-mentioned drawbacks. 2.0 wt% was used.

As is clear from the examples described later, the dual-acting octylamine acetate has a greater effect of lowering the viscosity of the slurry than the conventionally used tetradecylamine acetate, so that the uniform dispersibility of the raw material powder can be improved.

As is clear from Figures 1 and 6, the amounts added are Q,
There is no effect below 05 wt% ('2.0 wt%
If it is more than that, the viscosity will increase and the non-linear characteristics will deteriorate.

The element is made by wet mixing a mixture of zinc oxide and additive components (two pieces) with a binder such as polyvinyl alcohol (with octylamine acetate added as a partial dispersant), powdering, molding, and firing.

G Examples Example 1 Bismuth oxide (B
+10s), cobalt oxide (COlom), antimony oxide (Sb, O,), mangaf dioxide (Mn02),
Chromium oxide (crtos), silicon dioxide (SiOy),
0.5 to 1.5 m01 of nickel oxide (NiO) each
% to form a solid component.

The high yield of this solid component is 80 vot% + 60 voz
%, 40vO2%, water, a polyvinyl alcohol binder, and octylamine acetate were added and wet-mixed.

At this time, octylamine acetate was modified with zinc oxide (2 to Q, varying from 01 wt% to 10 wt%). On the other hand, as a comparative example, the conventionally used tetra 1: Wet mixing was carried out in the same manner as in Example 1 using desylamine acetate.

The viscosity of the slurry of Example 1 obtained by wet mixing is shown in Fig. 1 (=, and the comparative example is shown in Fig. 2. The viscosity can be reduced to about 1/10 or less compared to conventional products.

Example 2゜The slurry with a solid content of 60 vot% obtained in Example 1 was dried and granulated using a spray dryer, and the resulting granulated powder was made into a powder with a diameter of 8
ON1 cylindrical shape with a thickness of 30 m (-molded. This is 900 m thick)
After first firing at 1000°C to 1000°C, and after applying a second insulating material to the side surface, second firing was performed at 1000°C to 1250°C. Thereafter, heat treatment was performed at 500°C to 700°C. Both end faces were polished, and electrodes made of 1 Ni aluminum were placed on both end faces.

As a comparative example, the slurry obtained in the comparative example of Example 1 was treated in the same manner as above to obtain a resistor element.

As described above, there are two elements obtained by
Figure 6 shows the relationship between J (2, and C2).
L7) Figure 4 shows the variation in voltage when current is applied.

It is clear from FIG. 6 and FIG. 4 that the device of the present invention shown by the curve 1) has improved non-linear characteristics and has less variation in VlmA compared to the comparative example shown by the end of the curve.

Example 3゜The raw material powder of Example 1 (octylamine acetate as a partial dispersant was mixed with zinc oxide (2:Q, 1 wt%, jQwt
%.

5 and 0 wt% of each were wet mixed in the same manner as in Example 1, and a non-linear resistor element was obtained by the same method as in Example 2 (2).

As a comparative example, a non-linear resistor element was obtained using a dispersant (= conventional dodecylamine acetate) in the same manner as above (secondary method).

Tables 1 and 2 show the discharge withstand capacity of this device when a method wave of 2 m5ec was applied.

From Table 1 and Table 2 above, it is clear that the discharge durability of the products using the octylamine acetate of the present invention is improved.

Effects of the Invention In the present invention, since octylamine acetate is used as a dispersant, the viscosity of the wet-mixed slurry can be lowered. You can obtain granulated powder with stable properties,
It is possible to improve the characteristics of the element.

In addition, since the viscosity of the slurry is reduced, the dispersion time of the raw material powder can be shortened compared to the conventional method, which provides various excellent effects.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the amount of the dispersant of the present invention added and the viscosity of the slurry. FIG. 2 is a graph showing the relationship between the amount of a conventional dispersant added and the viscosity of a slurry. FIG. 6 is a graph showing the relationship between the amount of dispersant added and nonlinear characteristics. FIG. 4 is a graph showing voltage variations at VlmA. FIG. 5 is a graph showing the bulk density and water content when 10 samples of conventional granulated powder are sampled. Fig. 1 Fig. 3 □ Fig. 5 T fin 1j 7” (I riff 12 g2 Fig. Dispersion ripening value 1 Fig. 4

Claims (2)

[Claims] (1) A method for manufacturing a voltage non-linear resistor containing zinc oxide as a main component, which is characterized in that octylamine acetate is added as a dispersant when wet-mixing the raw material powder that is the solid component. A method for manufacturing a non-linear resistor element. (2) The method for manufacturing a voltage nonlinear resistor according to claim 1, characterized in that the amount of the octylamine acetate added is from 0.05 wt% to 2.0 wt% based on zinc oxide. .