IS 5921 Pt.3-1978
电子和电信设备用印刷电路用金属包覆基材规范第 III 部分酚醛纤维素纸覆铜层压板 PF-CP-Cu(高电级)
Specification for metal-clad substrates for printed circuits used in electronic and telecommunications equipment Part III Phenolic cellulose paper copper-clad laminate PF-CP-Cu (high electrical grade)