Patent ID: 9504149
Filing Date: 2016-11-22
CPC Classification: B32B,C25D,H05K,Y10T

Claim Text:
1. A surface treated copper foil comprising: at least one surface treated surface with a color difference ΔE*ab of 40 or more based on JIS Z 8730, and a difference between a top average Bt and a bottom average Bb in a brightness curve extending from an edge of the copper foil to a portion without the copper foil ΔB (ΔB=Bt−Bb) of 40 or more, after lamination of the surface treated surface to a polyimide having a ΔB (PI) defined as above of 50 or more and 65 or less before being laminated to the copper foil, wherein the brightness curve is obtained from an observation spot versus brightness graph of measurement results of the brightness of a photographed image of the copper foil through the polyimide with a CCD camera for the respective observation spots along the direction perpendicular to the extending direction of the observed copper foil.