Title:
DOUBLE-SIDED FLEXIBLE WIRING BOARD AND MANUFACTURE THEREOF
Document Type and Number:
Japanese Patent JP3687365
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To make conduction with high productivity and high reliability between wirings on both sides of a double-sided flexible wiring board, ensure high adhesion between an insulation layer (esp., polyimide layer) and conductive layers (esp., Cu layers) on both sides thereof, form wiring patterns by the finable additive method and avoid curling.
SOLUTION: A double-sided flexible wiring board has a laminate polyimide layer 3 composed of a first, second and third polyimide layers 3a, 3b, 3c between a lower and upper wiring layers 1, 2, the absolute value of the thermal linear expansion coefficient difference between a polyimide resin of the second polyimide layer 3b and metal materials of the wiring layers 1, 2 is within 5×10-6/K, and the third polyimide layer 3c is made of sulfo group-contg. polyimide. Metal plugs 7 filled in through-holes 6 formed through the laminate layer 3 by etching make conduction between the wiring layers 1, 2, and coverlays 4, 5 are disposed on the outsides of the wiring layers 1, 2.
Inventors:
Satoshi Takahashi
Toru Masuyama
Hideji Hagi
Toru Masuyama
Hideji Hagi
Application Number:
JP31521498A
Publication Date:
August 24, 2005
Filing Date:
November 05, 1998
Export Citation:
Assignee:
Sony Chemical Co., Ltd.
International Classes:
H05K3/28; B32B15/08; B32B15/088; B32B27/34; H05K1/03; H05K1/11; H05K3/16; H05K3/38; H05K3/42; (IPC1-7): H05K1/03; B32B15/08; B32B27/34; H05K1/11; H05K3/16; H05K3/28; H05K3/38; H05K3/42
Domestic Patent References:
| JP8250860A | ||||
| JP4176187A | ||||
| JP6326438A | ||||
| JP8294993A | ||||
| JP8107282A | ||||
| JP10256700A |
Attorney, Agent or Firm:
Taji U.S. Patent Office
Noboru Tajime
Tajime Keiko
Noboru Tajime
Tajime Keiko