PURPOSE: To improve adhesion to a metal layer and a peel strength without impairing an excellent heat resistance and a high mechanical strength which are inherent by a method wherein a molding material for a printed wiring is constituted of a highly syndiotactic styrene polymer having a polar group.

CONSTITUTION: A molding material for a printed wiring is constituted of syndiotactic styrene resin SPS having a polar group, as a component. The melting point of this SPS is 260 to 270°C and it is much more excellent in heat resistance than a usual atactic styrene polymer. A denatured one of this SPS is obtained, for instance, by introduction of the polar group by a copolymerization reaction at the time of polymerization, by introduction of the polar group at the time of stop of a polymerization reaction, by grafting with bipolar groups, etc. The material for the printed wiring obtained by using this denatured SPS is improved greatly in a peel strength without impairing an excellent heat resistance and a high mechanical strength which are inherent in the SPS, and it is given an excellent fire retardance in addition to these characteristics.