FLEXIBLE WIRING SUBSTRATE AND MANUFACTURE OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a flexible wiring substrate which controls generation of curl. SOLUTION: In a flexible wiring substrate wherein two or more layers of plastic films manufactured by extending in two directions of vertical and lateral directions are stacked, elliptic bodies having respective line expansion coefficients are formed on the coordinates at the portions corresponding with each other to the two plastic film surfaces located at both outer most layers. There is provided the relationship that the maximum value of the difference of the line expansion coefficients of the plastic films obtained by stacking the elliptic bodies so that the center matches the coordinate axes is 1.4×10<-5> (1/ deg.C) or less.