JPS6153161A - Voltage depending non-linear resistor ceramic composition - 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 Field of Industrial Application The present invention is directed to a 5rTLO3f that completely absorbs or removes abnormal voltage, noise, static electricity, etc. generated in electronic and electrical equipment.
The present invention relates to a voltage-dependent non-linear resistor ceramic composition for obtaining a voltage-dependent sandwiched linear resistor as a main component.

Conventional configurations and their obstacles Conventionally, they absorb abnormally high voltages (hereinafter referred to as surges) and remove noise in various electronic and electrical devices.

SiC/<Risk and ZnO-based TSUKU1NOSTAR, which have voltage-dependent linear resistance characteristics, were used to eliminate sparks. The voltage-current characteristics of such a (-nostar) can be expressed approximately as shown in the following equation.

Engineering = (V/C)LOL Here, I is current, ■ is voltage, C is a constant unique to Nostar, and α is a voltage nonlinear index.

SiC varistors have α of about 2 to 7, and ZnO-based IJ stars often have a of as high as 60. Does this type of varistor have excellent performance in absorbing relatively high voltages such as surges? However, due to its low dielectric constant and small specific capacitance, it has little effect on absorbing low voltages below the varistor voltage (for example, noise), and the dielectric loss angle (tan δ) is also 6. It's as big as ~1 ochi.

On the other hand, to eliminate these low voltage noises, semiconductor porcelain capacitors with an apparent dielectric constant of about 5X10' to 6X10' and a tan δ of around 1% are used by appropriately selecting the composition and firing conditions. There is. However, such semiconductor porcelain capacitors are used in electrical and electronic equipment because current exceeding a certain limit is applied to the element due to surges, etc. Therefore, varistors and capacitors are usually used in electrical and electronic equipment for the purpose of absorbing surges and eliminating noise. It is used in combination with other parts (such as a coil), and for example, a noise filter has such a structure.

FIG. 1 shows a general conventional noise filter circuit, and FIG. 2 shows a conventional noise filter circuit constructed by combining a varistor, a capacitor, and a coil.

Here, 1 is a coil, 2 is a capacitor, and 3 is a varistor.

However, the noise filter shown in Figure 1 is susceptible to surges, and the noise filter shown in Figure 2 has many parts and is relatively large, which is contrary to the trend toward miniaturization of overall equipment and increases costs. It had such drawbacks.

Purpose of the Invention Does the present invention solve the above-mentioned drawbacks of conventional surge absorption and noise removal? The purpose is to provide a porcelain composition that is suitable for eliminating risks, containing the functions of both a varistor and a capacitor, and having the combined function of surge absorption and noise elimination in one element. There is.

Structure of the Invention In order to achieve the above object, the present invention uses Sr with an atomic ratio of Sr and Ti of Sr/Ti=1050 to 0960.
T 1O3f 93000~99.995 mo/'%
, Y2O3woQ001~2000molti, and Co20
3tO○01~200゜mo/L/% and CuO'k o
oo 1-1000 mol, Ag2O'j (QOOl
~1000 mol% and dog○ total 0.001~1000
A voltage-dependent nonlinear resistor ceramic composition having molar ratios of Sr and Ti and an atomic ratio of Sr/Ti = 105
0~0950 5rTi○3'i 91000~99
．． 994 mole, Y mole 3 as 0001-2000 mole, CO□ mole i 0001-2000 mo/l,
%, Cuo as Qo01~1000 mo/l/%, Ag
2Of QOo 1-1000 mol%, MgO 0001-1000 mol%, B2O3, Nt○, Mo
5s.

BeO, Fe2O3, An203. L 120. C
rA, P bo * CaO, T i02 +P2
O5,5b203. The present invention relates to a voltage-dependent nonlinear resistor ceramic composition containing at least one type of oxide selected from the group consisting of V206 and a total of 0,001 to 2,000 molar ratios.

Description of examples EXAMPLES The present invention will be specifically described below with reference to Examples.

<Example> S rco3. T 1o2f S r and Ti were weighed so that the atomic ratio was Sr/Ti = 0980, pulverized and mixed in a ball mill etc. for about 20 minutes, dried and pulverized again, and 8QφX 50 (m
Temporarily mold into m). The above molded body'z was fired at 1200° C. for 4 hours and ground again for about 20 hours using a ball mill or the like to produce S r TiO3 as the main raw material.

Next, S rT i03. Y2O3, Co2O3, Cu
O, Ag2O, MgO.

Oyobi B2O3, Nip, Mo53. Boo, F.
e203. A.A. 03. L>20.

Cr203. PbO, CaO, Tt02. P2O5,
5b203. V2O5f was weighed to have the composition ratio shown in Table 1 below, mixed in a ball mill etc. for about 12 hours, and after drying, granulated by adding about iowt% of an organic binder of polyvinyl alcohol to the total weight. Thereafter, it is formed into a disk shape of 10φ×1-rrrIn) with a press pressure of 10t/cra.

After baking the above molded body in air at 1000°C for 2 hours,
Calcinate at approximately 1400°C for 2 hours in a reducing atmosphere of N2 (90%) + N2 (10%), then bake again in air for 1 hour.
After firing at 200° C. for 3 hours, four gold elements shown in FIG. 3 were obtained.

Next, a conductive paste If of silver or the like is applied to both planes of the element 4.
Electrodes 5.6 were formed by coating and baking at 550°C.

The characteristics of the device obtained by the above operations are all shown in Table 2 below.

Margin below (Table 2) Here, the characteristics of the device as a varistor are evaluated using the above-mentioned voltage-current characteristic formula % formula (% formula %) (where, engineering is the current, ■ is the voltage, C is a constant specific to the varistor, and α is a non-varistor This can be done by α and C in the linear index). However, since it is difficult to accurately measure C, in the present invention, the value of the varistor voltage per unit thickness (hereinafter referred to as V1mA/-) when 1mA of varistor current is passed, and a = 1 /fl og (V1om
A/V1mA) (However, vl. Saba is the varistor voltage when a varistor current of 10mA flows, vltnA is 1m
The characteristics of the varistor are evaluated based on the value of the varistor voltage (when a varistor current of A is applied).

Further, the characteristics as a capacitor are evaluated using the dielectric constant ε and the dielectric loss angle La1lδ at a measurement frequency of 1.

As shown above, the basically required lister characteristics and capacitor characteristics are expressed by high resistance barriers that occur at the grain boundaries of the element body.

Therefore, additives that increase the resistance only at the grain boundaries without increasing the resistance inside the grains are effective.

Y2O3, Co as additives to 5rTi○3. 03. C
uO.

By adding Aq20 and MqO'jc, an element body having a relatively low varistor voltage and a high dielectric constant can be obtained.

Furthermore, P2O3, Ni○, MoO3, B e
o, F e 203.

Lt. O, Cr2O3, PbO, CaO, Tio2.
P2O5,5b203°A22o3. By adding Y2O5, jan δ can be reduced without changing the varistor voltage.

Moreover, if the amount of each addition is less than the specified amount range, no effect will be exhibited, and if it exceeds the specified amount range, the varistor voltage will increase rapidly and the dielectric constant will decrease, which is not desirable.

Furthermore, the Sr/Ti 2 ratio greatly influences semiconductor formation, and outside the specified range, semiconductor formation is suppressed and the dielectric constant becomes small.

Further, in the examples, only the negative part was shown for combinations of additives, but it was confirmed that any combination had the same effect as long as it was within the specified range.

As described above, according to the present invention, the functions of both a varistor and a capacitor can be obtained simultaneously.

In the conventional filter circuit shown in FIG. 1, the output situation curve C is obtained for the noise input shown in FIG. 5, and the noise is not removed sufficiently.

In the conventional noise filter circuit including a varistor shown in FIG. 2, the output situation curve B is obtained for the noise input A shown in FIG. 5, and noise is removed, but the number of components is large.
It is relatively large and costly.

Therefore, when a circuit as shown in Fig. 4 was made using the element according to the present invention, the output situation curve B was obtained for the noise input A shown in Fig. 5, and the noise could not be sufficiently removed. Ta.

In FIG. 4, 7 is an element according to the present invention, and 8 is a coil.

Effects of the Invention As mentioned above, the element using the porcelain composition gold according to the present invention has unprecedented advantages (risk and combined function of a capacitor?
Moreover, it completely simplifies the conventional noise fill circuit and contributes to miniaturization, high performance, and low cost. is extremely valuable.

[Brief explanation of the drawing]

Are Figures 1 and 2 conventional noise filter circuits?
3 is a cross-sectional view of an element using the ceramic composition according to the present invention, FIG. 4 is a diagram showing a noise filter circuit using the element sound of FIG. Input noise and output status due to noise filter circuit using ? FIG. Name of agent: Patent attorney Toshio Nakao and 1 other M1
Fig. 3, 5 Fig. 4 Fig. 5 One round liquid number (r'It-h)

Claims (2)

[Claims] (1) The atomic ratio of Sr and Ti is Sr/Ti=1.050
~0.950 SrTiO_3 93.00099.9
95 mol% and Y_2O_3 from 0.001 to 2.000
mol%, Co_2O_3 0.001 to 2.000 mol%, CuO 0.001 to 1.000 mol%, A
A voltage-dependent nonlinear resistor ceramic composition containing 0.001 to 1.000 mol% of g_2O and 0.001 to 1.000 mol% of MgO. (2) The atomic ratio of Sr and Ti is Sr/Ti=1.050
~0.950 SrTiO_3 from 91.000 to 99.00.
994 mol% and Y_2O_3 from 0.001 to 2.00
0 mol% and 0.001 to 2.000 Co_2O_3
mol%, CuO 0.001 to 1.000 mol%,
0.001 to 1.000 mol% of Ag_2O and MgO
0.001 to 1.000 mol%, B_2O_3, N
iO, MoO_3, BeO, Fe_2O_3, Li_2
O, Cr_2O_3, PbO, CaO, TiO_2, P
_2O_5, Sb_2O_3, Al_2O_3, V_2
A voltage-dependent nonlinear resistor ceramic composition containing 0.001 to 1.000 mol% of at least one oxide selected from the group consisting of O_5.