JPS59111201A - High dielectric constant porclain 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 relates to a high dielectric constant ceramic composition having a low sintering temperature and suitable as a material for a ceramic capacitor.

Conventional Structures and Problems The characteristics that dielectric materials should have vary depending on the application, but ceramic capacitors are required to have a large dielectric constant and resistivity, a small dielectric loss tangent, and a low sintering temperature.

A large dielectric constant is an important condition for downsizing the device. A low sintering temperature has great industrial value, as it allows the use of inexpensive materials for the firing furnace and requires less energy for firing when firing porcelain materials. In addition, in multilayer ceramic capacitors,
If the sintering temperature is low, a relatively inexpensive electrode material containing silver as a main component can be used as the internal electrode, so the price of the capacitor can be significantly reduced.

Conventionally, barium titanate-based porcelain has been used as a material for high dielectric constant ceramic capacitors. but,
This material has a high sintering temperature of 1300 to 1400'C, so when manufacturing multilayer ceramic capacitors, expensive platinum or palladium suitable for the sintering temperature is used as the main component and j6 part heavy pole is used. There are drawbacks that must be
Ta.

Purpose of the Invention The present invention improves the above-mentioned drawbacks and reduces the sintering temperature to 1oOo0C.
The object of the present invention is to provide a high dielectric constant ceramic composition having a low resistivity and a high resistivity.

Structure of the Invention The composition of the present invention comprises Pb(Nip NbH) x (FeH
NbH) y (Ff32I3W Akira) z O3r table spoiler,
Kak m ratio Kao, o 11, z≦0.40, 0.45
≦y≦o, so and 0.05≦2≦0.60. (However, the main component is a composition within the range of
Cr), cobalt (Go).

and oxides (Mn02, Cr2O3, Coo, Li2) of at least one element in lithium (Li).
The above objective was achieved by containing 0.01 to 1.5% by weight calculated as the weight of 0).

Explanation of Examples Raw materials include PbO, NiO, Fe2o3. Nb2O5,
W%.

MnO2, Cr203, Coo and L12CO3 were weighed to have the composition ratio shown in the table below and mixed in a wet manner. After drying each mixture at 750°C
After calcination for 2 hours, it was wet-pulverized in a ball mill.

After drying, the aqueous solution of polyvinyl alcohol was used as a binder to form a cylinder with a diameter of 13FJJ and a length of about 8 cm. After incinerating the binder, the product was placed in a magnesia porcelain container and heated at a temperature within the range of 840 to 980°C. It was baked for 2 hours. Each fired porcelain was cut to a thickness of 1 mm, and after evaporating 0r-Au on both sides, the dielectric constant εr and the dielectric loss tangent were set to 1 KHz.

Measured at room temperature in IV/mm. Further, the specific resistance was measured in I KV/mm at room temperature. The results are shown in the table below.

(Margin below) In the table above, No. 1, 6, 11. 16, 23, 27° 3o, 3
Each sample of e, 3s, 40, 41.45 is outside the scope of the present invention, and NO2~5,7~10.12~15.1
7~22.24~26°28.29.31~35.37
．． Samples 39.42-44.46-49 are examples within the scope of the present invention. As is clear from the above table, the porcelain composition within the scope of the present invention can be made by containing one or more elements among Mn, Or, Go, and LiO as a subcomponent to the main component. Furthermore, the specific resistance can be increased and the dielectric loss tangent can be decreased. Furthermore, the composition of the present invention has a large dielectric constant (8140~
24100) and low firing temperature (840-9800C)
) also maintains the characteristics of the main component composition.

Note that compositions in which the content of subcomponents exceeds 1.5% by weight and compositions in which the content of subcomponents is less than 1% by weight are excluded from the scope of the present invention because they are ineffective in improving specific resistance.

In addition, the composition range of the main component is such that a dielectric constant of 8,000 or more is obtained and the firing temperature is 10,000C or less (X=0.
01~0.40, y=o, a5~o, so.

z = Qos ~ o, so).

Although the above-mentioned materials were used as raw materials in the examples, it goes without saying that the same effect can be obtained by using other oxides or raw materials that become oxides by firing, such as carbonates.

Effects of the Invention The composition of the present invention has a large dielectric constant, a relatively small dielectric loss tangent, and a large specific resistance, so it is suitable as a material for ceramic capacitors, and it can be fired at a low temperature of 10,000 C or less, so it is suitable for use in firing kettles. It has great industrial value, as it allows the use of inexpensive furnace materials and requires less energy for firing. When used in a multilayer ceramic capacitor, since the sintering temperature is low, relatively inexpensive internal electrodes such as silver can be used, and the price of the capacitor can be reduced.

Claims (1)

[Claims] Pb(Nil,6Nb213)x(FeV2NbH)
, (Fed Wy, )203, and the composition ratio is 0.
．． 01≦x40.40゜0.45≦y≦0.80 and 0.05≦2≦0.50 (however, x+y+z=1), and further contains manganese (M
Oxides (Mn02, Cr2 o3.Coo,
A high dielectric constant ceramic composition containing 0.01 to 1.5% by weight of Li20).