Abstract: The invention provides a heat-resistant, low-dielectric polymeric material that is preferably a copolymer in which a non-polar &agr;-olefin base polymer segment and a vinyl aromatic copolymer segment are chemically combined with each other, and that is a thermoplastic resin showing a multi-phase structure in which a dispersion phase formed by one segment is finely dispersed in a continuous phase formed by another segment. It is thus possible to achieve a polymeric material that is excellent in heat resistance, has high strength, and has a low dielectric constant and a reduced dielectric loss, and so is suitable for an electrical insulating material for high-frequency purposes.

Abstract: The invention has for its object to provide a composite dielectric material having any desired dielectric constant selectable from a relatively wide range in a high-frequency band and a low dielectric loss tangent, and a film, substrate, electronic part or molded or otherwise formed article using the same. To accomplish this object, there is provided a composite dielectric material composition comprising a heat-resistant, low-dielectric polymeric material that is a resin composition comprising one or two or more resins having a weight-average absolute molecular weight of at least 1,000, wherein the sum of carbon atoms and hydrogen atoms in said composition is at least 99%, and some or all resin molecules have a chemical bond therebetween, and a filler. A film, substrate, electronic part or molded or otherwise formed article is obtained using this composition.

Abstract: A delay line component having merits of small physical size and small insertion loss in a radio frequency. The delay line component with coaxial cable structure includes a center conductor, a dielectric which surrounds the center conductor and an outer conductor which is formed outside the dielectric. The dielectric is made of a ceramic dielectric with a large dielectric constant.