| 摘要 |
PROBLEM TO BE SOLVED: To obtain a dielectric porcelain compsn. of a uniform and very small grain diameter ensuring high density of dielectric porcelain. SOLUTION: Niobium oxide as an accessory constituent is incorporated by 0.3-5.0 pts.wt. (expressed in terms of Nb2 O3 ) into 100 pts.wt. principal compsn. contg. <=5mol% Bi2 O3 based on 100mol% compsn. represented by the general formula x[(BaO)1-m (CaO)m ].yTiO2 .zR2 O3 , wherein R is one or more kinds of rate earth elements selected from among La, Pr, Nd and Sm, 0.01<=m<=0.50, (x), (y) and (z) show molar ratio, x+y+z=1 and (x), (y) and (z) are within the range defined by (a) to (e) in the table. |
