公开(公告)号：EP0498898A1

公开(公告)日：1992-08-19

申请号：EP91915723.0

申请日：1991-09-03

Applicant: CHISSO CORPORATION

Inventor： HASE, Hiroaki ,  KIKUTA, Kazutsune ,  TAKAHASHI, Atsushi ,  KONOTSUNE, Shiro

IPC: H05K1/03 ,  H05K3/30 ,  H05K3/38 ,  B32B15/08

CPC classification number: B32B15/08 ,  B32B27/281 ,  B32B2307/30 ,  B32B2307/51 ,  B32B2379/08 ,  B32B2457/08 ,  H05K1/0346 ,  H05K1/036 ,  H05K1/0393 ,  H05K2201/0154 ,  H05K2201/0358 ,  H05K2201/068 ,  Y10T428/24917 ,  Y10T428/31678 ,  Y10T428/31681

Abstract: A flexible printed circuit board having a polyimide film formed by a method wherein a polyimide precursor is directly applied on a metallic conductor foil, dried, heated and cured. The polyimide film comprises two or more laminated layers. The coefficient of thermal linear expansion of at least one polyimide layer except for the first polyimide layer in contact with the metallic conductor foil is larger than that of the first polyimide layer. Also, the thicknesses and curls of the laminated layers of the polyimide film satisfy the following equations: 3.0 n-1 X t n n-1 > t n , where t n is the thickness (µm) of the outermost polyimide layer (n-th layer), t n-1 is the thickness (µm) of from the first to the (n-1)-th layers, and Q n-1 is twice the value (cm) of the radius of curvature of the curl of the film of from the first to the (n-1)-th layers. This board does not curl just after the curing, and even after forming a circuit by etching.

Abstract translation: 一种柔性印刷电路板，其具有通过将聚酰亚胺前体直接涂布在金属导体箔上的方法形成的聚酰亚胺膜，干燥，加热固化。 聚酰亚胺膜包含两层或多层叠层。 除了与金属导体箔接触的第一聚酰亚胺层之外的至少一个聚酰亚胺层的热线性膨胀系数大于第一聚酰亚胺层的热线性膨胀系数。 此外，聚酰亚胺膜的层叠层的厚度和卷曲满足以下等式：3.0 tn，其中tn是最外层聚酰亚胺层（第n层）的厚度（μm），tn-1是从第一至第（n-1）层的厚度（μm） 层和Qn-1是从第一层到第（n-1）层的膜的卷曲的曲率半径的值（cm）的两倍。 该板在固化后即使在通过蚀刻形成电路之后也不会卷曲。