| 摘要 |
PROBLEM TO BE SOLVED: To provide a laminate for a wiring substrate which has a low coefficient of linear expansion and also is excellent in heat resistance, especially one useful for the applications of substrates and the like for FPCs and HDD suspensions. SOLUTION: The laminate for the wiring substrate is the one having a metal layer on one surface or both surfaces of a polyimide resin layer, wherein the polyimide resin layer has two or more different resin layers, at least one layer of the resin layer is a polyimide resin layer (i) containing 10-85 mol% of a specific structural unit, at least one layer consists of a polyimide resin layer (ii) having a lower glass transtion temperature than that of the polyimide resin layer (i), and the thickness of the polyimide resin layer (i) is≥50% of the total thickness of the polyimide resin layers. COPYRIGHT: (C)2009,JPO&INPIT |
