Microwave dielectric ceramic composition
US5444028A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1994 |
| Grant date | Aug 22, 1995 |
| Priority date | — |
| Expiry date | Nov 16, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/465
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In order to obtain a microwave dielectric ceramic composition having a high dielectric constant (.epsilon.r) and a large Q value and having a temperature coefficient of resonance; frequency (.tau.f) which is close to zero, the present invention is directed to a microwave dielectric ceramic composition expressed by a composition formula of w.multidot.Li.sub.2 O-x.multidot.CaO-y.multidot.A.sub.2 O.sub.3 -z.multidot.TiO.sub.2, wherein w, x, y and z are respectively in the ranges of 0.0 mole %<w.ltoreq.25.0 mole %, 0.0 mole %.ltoreq.x.ltoreq.50.0 mole %, 0.0 mole %<y.ltoreq.30.0 mole %, 0.0 mole %<z.ltoreq.80.0 mole % where w+x+y+z=100 mole %, and not more than 5 parts by weight of any one of ZnO, CoO, NiO and MgO is contained therein, and wherein A is selected from Sm and Nd.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.