Gedruckte Schaltung auf flexibler Leiterplatte und Verfahren zu ihrer Herstellung

摘要

A flexible double-sided copper-clad printed-circuit base board comprises two copper foils and a resin layer formed directly therebetween, the resin layer being a composite material comprising a polyimide having recurring units of the formula: wherein some of the groups R<1> are bivalent aromatic hydrocarbon groups of the formula (in which Y is -O-, -CO-, -SO2- or -CH2-) and the others are bivalent aromatic groups of the formula and a polyimide-silicone of formula: in which R<2> is a monovalent aliphatic hydrocarbon group having at most 5 carbon atoms or a monovalent aromatic hydrocarbon group having at most 9 carbon atoms; R<3> is a tetravalent aromatic hydrocarbon group; R<4> is a bivalent aromatic hydrocarbon group; R<5> is a siloxane chain; R<6> is a bivalent aliphatic hydrocarbon having 3 to 5 carbon atoms or a bivalent aromatic hydrocarbon group having 6 to 9 carbon atoms; r is 2 or 3; the molar ratio of x : y is in the range of 97-60 : 3-40; and the molar ratio of m : n is in the range of 50-100 : 50-0.