JP3089371B2 - Voltage non-linear resistance composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage non-linear resistance composition containing zinc oxide as a main component and a sintered body itself having voltage non-linearity.

[0002]

2. Description of the Related Art Heretofore, the load life characteristics of zinc oxide (ZnO) varistors have not always been sufficient depending on the application. As a solution, paste glass frit was applied to a sintered body made of zinc oxide, and heat treatment was applied to diffuse the glass to protect and reinforce grain boundaries. However, there are problems such as a decrease in electric characteristic values due to the heat treatment and a large pulse deterioration. Furthermore, since the amount of the glass frit applied to the sintered body has a large influence on the varistor voltage, the voltage non-linear coefficient, and the load life characteristic, it is necessary to strictly control the amount of the paste-like glass frit to be applied. If the application amount control is not performed sufficiently, there is a problem that the characteristics of the manufactured sintered bodies vary widely and the production yield is deteriorated. Further, when the shape of the sintered body is large, the glass diffusion becomes insufficient, the glass is not uniformly diffused to the inside of the sintered body, and a remarkable improvement in load life characteristics cannot be obtained.

In view of the above-mentioned glass diffusion method, a glass addition method of adding a glass frit such as bismuth borosilicate to a raw material before sintering and sintering at a temperature of 1100 to 1300 ° C. has been attempted.

[0004]

According to the above-mentioned glass addition method, the amount of glass frit added to the raw material can be easily quantified, the manufacturing process is complicated by the glass diffusion method, the characteristic value is degraded by heat treatment, the load life characteristic and the varistor voltage are reduced. There is an advantage that variations in characteristic values such as are improved.

[0005] However, although the voltage nonlinear resistance composition thus prepared has improved load life characteristics against DC, it has problems such as large pulse deterioration, and very high varistor voltage due to low temperature firing.

[0006] Recently, zinc oxide varistors have been widely used for absorbing surges. However, they are characterized by small pulse degradation and excellent load life characteristics against continuous application of current such as direct current and alternating current. It is a necessary condition for use.

[0007] Therefore, even in the above-mentioned glass addition method, there is a problem that the pulse deterioration is small and both conditions having excellent load life characteristics cannot be sufficiently satisfied. The present invention solves the above-mentioned problems, and the components and the composition ratio of bismuth borosilicate glass frit to be added to zinc oxide, the amount of addition, and the combination thereof can sufficiently improve both pulse life characteristics and load life characteristics. It is an object of the present invention to provide a voltage non-linear resistance composition satisfying the above conditions for absorbing surge.

[0008]

The voltage non-linear resistance composition of the present invention is a voltage non-linear resistance composition in which a sintered body containing zinc oxide as a main component has voltage non-linearity. Bismuth in the form of Bi ₂ O ₃ is 0.05 to 2.0 mol%, and antimony is 0.05 to 2.0 mol% in the form of Sb ₂ O _3. , Cobalt to CoO
0.1 to 2.0 mol% in terms of the form of manganese;
0.1 to 3.0 mol% in terms of O, nickel is N
0.05 to 2.0 mol% in terms of the shape of iO, 0.05 to 2.0 mol% in terms of titanium in the form of TiO _2, in terms of silicon in the form of SiO ₂ 0.05 ~ 3.0 mol%,
Conversion of aluminum to Al ₂ O ₃ form
Bismuth borosilicate glass frit containing 0.5 mol% and manganese oxide of 1 to 10 wt% is added in an amount of 0.2 to 1.0 wt%.

[0009] It should be noted that the two components of nickel oxide and glass frit containing manganese oxide in bismuth borosilicate glass can satisfy both characteristics of pulse life and load life at high temperature. It is thought that there is.

[0010]

The reason why the components to be added to zinc oxide as the main component of the voltage non-linear resistance composition and the composition ratio thereof are selected as described above is that any one of the voltage non-linear resistance compositions formed by adding the composition is used. In this case, both the pulse life and the load life at high temperature can be satisfied. In other words, if the composition of the component added to the main component zinc oxide is out of the range of the present invention, these target values cannot be achieved.

[0011]

EXAMPLES Specific examples of the present invention will be described below along with comparative examples.

Experimental Example 1 First, high-purity zinc oxide (ZnO), bismuth oxide (Bi ₂ O ₃ ), antimony oxide (Sb ₂ O ₃ )
Cobalt oxide (CoO), manganese oxide (MnO), nickel oxide (NiO), titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), and aluminum oxide (Al ₂ O ₃ ) were prepared.

Next, in preparing bismuth borosilicate glass frit to be added to zinc oxide, 0.5 mol% of bismuth oxide, 0.5 mol% of antimony oxide, 0.5 mol% of cobalt oxide, and 0.5 mol of manganese oxide %, Nickel oxide 0.5 mol%, titanium oxide 0.5 mol%, silicon oxide 0.5 mol%, aluminum oxide 0.05 mol%, and the amount of manganese oxide contained in the bismuth borosilicate glass frit Was weighed to the amount shown in Table 1.

Then, each of bismuth borosilicate glass frits having different contents of manganese oxide is added to zinc oxide in an amount of 0.5% by weight and mixed well.
% Solution as a binder and granulated. Next, the obtained mixture is formed into a disk having a diameter of 14.0 mm, and the obtained molded product is fired in air at 1250 ° C. for 2 hours to prepare a sample of a resistance composition of a sintered body. did. After applying an electrode material paste containing silver to the front and back surfaces of each of the prepared resistance composition samples, baking is performed at a temperature of 850 ° C. to form electrodes, and lead wires are formed on the electrodes with silver-containing solder. A voltage non-linear resistance composition was prepared.

The varistor voltage per unit (V1 mA / mm), the voltage non-linear coefficient (α), the high-temperature DC load for each of the thus formed voltage non-linear resistance compositions having electrodes on the front and back surfaces. The electrical characteristics of the varistor voltage change rate (ΔV1mA) due to the life and high-temperature AC load life and the varistor voltage change rate (ΔV1mA) due to the pulse life were measured.

The varistor voltage is measured by a constant current power supply, and the voltage nonlinear coefficient is

[0017]

(Equation 1)

The high-temperature DC load life and the high-temperature AC load life are measured by applying a DC power of 0.6 W or an AC power of 0.6 W for 1000 hours at an ambient temperature of 70 ° C. (8 × 20) was the 200A current microsecond waveform measured repeatedly applied 10 ^three times.

[0019]

[Table 1]

Note that those marked with * in Table 1 are out of the scope of the present invention, and others are within the scope of the present invention.

As is apparent from Table 1, the amount of manganese oxide contained in the bismuth borosilicate glass frit is 1 to 5.
It was confirmed that each electric property was excellent in the range of 10% by weight. When the amount of manganese oxide in the bismuth borosilicate glass frit is less than 1% by weight, the voltage nonlinear coefficient is excellent, but the pulse life characteristics are not improved, and the amount of manganese oxide in the bismuth borosilicate glass frit is not increased. Exceeds 10% by weight, the voltage nonlinear coefficient decreases, the high-temperature load life characteristics and the deterioration of the pulse life increase, and the desired electrical characteristics cannot be obtained.

EXPERIMENTAL EXAMPLE 2 Bismuth oxide, antimony oxide, cobalt oxide, manganese oxide, nickel oxide, titanium oxide, silicon oxide, and aluminum oxide were varied in composition ratio according to Experimental Example 1, and further contained manganese oxide. Bismuth borosilicate glass frit was added in an amount of 0.5% by weight with respect to zinc oxide, and each voltage non-linear resistance composition was prepared in the same manner as in Experimental Example 1.

For each of the prepared voltage non-linear resistance compositions, the varistor voltage, voltage non-linear coefficient, high temperature DC load life, high temperature AC load life,
Measurement of each electrical property of pulse life revealed that each composition in the bismuth borosilicate glass frit added to zinc oxide was within the range of the present invention, that is, the content of bismuth oxide was 0.0%.
5 to 2.0 mol%, 0.05 to 2.0 mol of antimony oxide
Mol%, cobalt oxide 0.1 to 2.0 mol%, manganese oxide 0.1 to 3.0 mol%, nickel oxide 0.0
5 to 2.0 mol%, titanium oxide is in the range of 0.05 to 2.0 mol%, silicon oxide is in the range of 0.05 to 3.0 mol%, and aluminum oxide is in the range of 0.001 to 0.5 mol%. A voltage nonlinear resistance composition using bismuth borosilicate glass frit containing manganese oxide in the range of 1 to 10% by weight has excellent voltage nonlinear coefficient, pulse life characteristic,
In addition, high temperature load life characteristics were shown.

As described above, when each of the above-mentioned compositions is out of the composition range of the present invention, one of the voltage nonlinear coefficient, the high-temperature DC load life, the high-temperature AC load life, and the pulse life decreases,
Or, the desired electrical characteristics cannot be obtained due to deterioration.

Experimental Example 3 First, high-purity zinc oxide (ZnO), bismuth oxide (Bi ₂ O ₃ ), antimony oxide (Sb ₂ O ₃ )
Cobalt oxide (CoO), manganese oxide (MnO), nickel oxide (NiO), titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), and aluminum oxide (Al ₂ O ₃ ) were prepared.

Next, with respect to zinc oxide, bismuth oxide 0.1.
5 mol%, antimony oxide 0.5 mol%, cobalt oxide 0.5 mol%, manganese oxide 0.5 mol%, nickel oxide 0.5 mol%, titanium oxide 0.5 mol%, silicon oxide 0.1 mol %, Aluminum oxide 0.05 mol%, and manganese oxide content in the bismuth borosilicate glass frit were weighed to be 10% by weight.

Then, bismuth borosilicate glass frit was added to zinc oxide in the amount shown in Table 2, and after sufficient mixing, granulation was performed by adding a 5% PVA solution as a binder. Then, the obtained mixture was 14.0 m in diameter.
m in the shape of a disc, and the obtained molded product is
The sintered body was fired at 0 ° C. for 2 hours to prepare a resistance composition sample of a sintered body. After the electrode material paste containing silver was applied to the front and back surfaces of each of the prepared resistance composition samples, the temperature was set to 85.
The electrode was formed by baking at 0 ° C., and a lead wire was formed on the electrode by using a solder containing silver to prepare a voltage non-linear resistance composition.

For each of the voltage non-linear resistance compositions having electrodes on the front and back surfaces prepared in this manner, the varistor voltage, voltage non-linear coefficient, high-temperature DC load life, high temperature Each characteristic of the AC load life and the pulse life was measured, and the results are shown in Table 2.

[0029]

[Table 2]

Note that those marked with * in Table 2 are out of the scope of the present invention, and others are within the scope of the present invention.

As is clear from Table 2, the amount of bismuth borosilicate glass frit added to zinc oxide is 0.2 to
It was confirmed that each electric property was excellent in the range of 1.0% by weight. When the amount of bismuth borosilicate glass frit added to the zinc oxide is less than 0.2% by weight, the pulse life characteristics are excellent, but the high temperature load life characteristics are not improved, and the borosilicate added to the zinc oxide is not improved. When the amount of bismuth glass frit exceeds 1.0% by weight, the high-temperature load life characteristics are improved, but on the other hand, the voltage non-linear coefficient decreases, the pulse life deteriorates, and the desired characteristics are obtained. Absent.

The present invention is not limited to this, and the composition may further include magnesium oxide (M
gO), chromium oxide (Cr ₂ O ₃ ), lead oxide (PbO)
Etc. may be added. By adding these, the performance such as pulse life and high temperature load life can be further improved.

[0033]

As described above, according to the present invention, the zinc oxide varistor exhibits excellent characteristics against surges, and has excellent high-temperature load life characteristics and pulse life characteristics without impairing these characteristics. This has the effect of providing a voltage non-linear resistance composition.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01C ^7/ 02-7/22 C04B 35/453

Claims (1)

(57) [Claims] A sintered body containing zinc oxide as a main component itself is a voltage non-linear resistance composition having voltage non-linearity, and bismuth is formed in the form of Bi ₂ O ₃ with respect to zinc oxide as a main component. 0.05 to 2.0 mol% in terms of Sb ₂ O ₃
0.05 to 2.0 mol% in terms of
0.1 to 2.0 mol% in terms of oO, 0.1 to 3.0 mol% in terms of manganese in terms of MnO, and 0.05 to 2 in terms of nickel in terms of NiO. 2.0 mole%, 0.05 to 2.0 mol% in terms of titanium in the form of TiO _2,
Silicon is converted to SiO _{2 in} a form of 0.05 to 3.0 mol%, and aluminum is converted to Al ₂ O _{3 in} a form of 0.001%.
Bismuth borosilicate glass frit containing 0.2 to 1.0 mol% and manganese oxide 1 to 10% by weight.
A voltage non-linear resistance composition, wherein the composition is added by weight%.