Dielectric ceramic, resin-ceramic composite material, electrical part and antenna, and manufacturing method thereof

A resin-ceramic composite material, comprising a mixture of a powder of a dielectric ceramic and an organic polymer resin, wherein the organic polymer resin is polyphenylene sulfide, and

• wherein the dielectric ceramic is one, in which, to a main composition expressed by xBaO·yNd2O3·zTiO2·wBi2O3, wherein
• 0.13≦x≦0.20;
• 0.28≦y≦0.35;
• 0.33≦z≦0.45;
• 0.09≦w≦0.15;
• and
• x+y+z+w=1,
• La, Ce, Pr, Nb, Zn, and Sr as constituent elements are included with amounts ranging 2 to 5 mass % for La, 1 to 2 mass % for Ce, and 0.03 to 1 mass % for each of Pr, Nb, Zn and Sr, and wherein all ceramics as a whole, including the above main composition, make up 100 mass %.

A resin-ceramic composite material, comprising a mixture of a dielectric ceramic powder, and polyphenylene sulfide with a weight average molecular weight of not less than 35,000 and a molecular weight at a maximum frequency in molecular weight distribution of not less than 31,000, wherein the dielectric ceramic is one, in which, to a main composition expressed by xBaO·yNd2O3·zTiO2·wBi2O3, wherein

• 0.13≦x≦0.20;
• 0.28≦y≦0.35;
• 0.33≦z≦0.45;
• 0.09≦w≦0.15;
• and
• x+y+z+w=1,
• La, Ce, Pr, Nb, Zn, and Sr as constituent elements are included with amounts ranging 2 to 5 mass % for La, 1 to 2 mass % for Ce, and 0.03 to 1 mass % for each of Pr, Nb, Zn and Sr, wherein all ceramics as a whole, including the above main composition, make up 100 mass %.

A method for producing an electrical part with a resin-ceramic composite material, comprising steps of:

• molding the resin-ceramic composite material obtained by mixing a dielectric ceramic powder with a mean particle diameter of not more than 6 μm, and polyphenylene sulfide, by an injection-molding, wherein the dielectric ceramic powder is one, in which, to a main composition expressed by xBaO·yNd2O3·zTiO2·wBi2O3, wherein
• 0.13≦x≦0.20;
• 0.28≦y≦0.35;
• 0.33≦z≦0.45;
• 0.09≦w≦0.15;
• and
• x+y+z+w=1,
• La, Ce, Pr, Nb, Zn, and Sr as constituent elements are included with amounts ranging 2 to 5 mass % for La, 1 to 2 mass % for Ce, and 0.03 to 1 mass % for each of Pr, Nb, Zn and Sr, and wherein all ceramics as a whole, including the above main composition, make up 100 mass %;
• removing a surface skin layer consisting of only polyphenylene sulfide that is formed on the surface of the molded article;
• and
• plating thereon.

A method for producing an antenna with a resin-ceramic composite material, comprising steps of:

• molding the resin-ceramic composite material obtained by mixing a dielectric ceramic powder with a mean particle diameter of not more than 6 μm, and polyphenylene sulfide, by an injection-molding, wherein the dielectric ceramic powder is one, in which, to a main composition expressed by xBaO·yNd2O3·zTiO2·wBi2O3, wherein
• 0.13≦x≦0.20;
• 0.28≦y≦0.35;
• 0.33≦z≦0.45;
• 0.09≦w≦0.15;
• and
• x+y+z+w=1,
• La, Ce, Pr, Nb, Zn, and Sr as constituent elements are included with amounts ranging 2 to 5 mass % for La, 1 to 2 mass % for Ce, and 0.03 to 1 mass % for each of Pr, Nb, Zn and Sr, and wherein all ceramics as a whole, including the above main composition, make up 100 mass %;
• removing a surface skin layer consisting of only polyphenylene sulfide that is formed on the surface of the molded article;
• and
• plating thereon.