Abstract: A dielectric material based on BaO-RE.sub.2 O.sub.3 -TiO.sub.2 is disclosed, which has a relatively high relative permittivity .epsilon..sub.r, a small absolute value of the temperature coefficient of resonance frequency .tau..sub.f and a high coefficient of unloaded quality Q.sub.u. Processes for producing the dielectric material are also disclosed. The dielectric material comprises 100 parts by weight of main ingredients having a composition represented by xBaO-yRE.sub.2 O.sub.3 -zTiO.sub.2 (wherein RE represents a rare earth element and x+y+z=100) and up to 5 parts by weight of at least one alkali metal oxide. This alkali metal oxide serves to improve .epsilon..sub.r and Q.sub.u without a considerable sacrifice of .tau..sub.f. The RE preferably consists of samarium or a combination of samarium with neodymium and/or lanthanum.

Abstract: A dielectric material is disclosed which has a small absolute value of the temperature coefficient of resonance frequency and a high coefficient of unloaded quality. Also disclosed are a process for producing the dielectric material and multilayer and other circuit boards containing the dielectric material. The dielectric material is a highly densified material having a water absorption lower than 0.1%, which is obtained by mixing 95.5 to 99.5 percent by weight mixture of a glass frit and a strontium compound with 0.5 to 4.5 percent by weight titanium dioxide, compacting the resultant mixture, and sintering the compact at a relatively low temperature around 930.degree. C. This dielectric material is a glass ceramic containing strontium anorthite (SrAl.sub.2 Si.sub.2 O.sub.8) as the main crystalline phase, and may contain the TiO.sub.2, which remains unchanged after sintering. The absolute value of the temperature coefficient of resonance frequency of the dielectric material is 20 ppm/.degree. C.