Method for manufacturing double-sided flexible printed board
View Patent ↗A double-sided flexible printed board is manufactured by: (a) forming a polyimide precursor layer on a metal layer; (b) forming an upper circuit layer on the polyimide precursor layer by a semi-additive technique; and (c) imidating the polyimide precursor layer to form a polyimide insulating layer.
1. A method for manufacturing a double-sided flexible printed board, comprising the following steps of:
(A) forming a polyimide precursor layer on a metal layer;
(B) forming an upper circuit layer on the polyimide precursor layer by a semi-additive technique, leaving the polyimide precursor layer partially exposed at the upper circuit layer side; and
(C) after step (B), imidating the partially exposed polyimide precursor layer to form a polyimide insulating layer.
2. The method according to claim 1 , wherein step (M) in which the formation of a through hole for ensuring conductivity between the metal layer and the upper circuit layer is performed between step (B) and step (C) or subsequent to step (C).
3. A method for manufacturing a double-sided flexible printed board, comprising the following steps of:
(A) forming a polyimide precursor layer on a metal layer;
(B) forming an upper circuit layer on the polyimide precursor layer by a semi-additive technique, leaving the polyimide precursor layer partially exposed at the upper circuit layer side; and
(C) imidating the polyimide precursor layer, while the polyimide precursor layer includes the upper circuit layer that has been formed on the polyimide precursor layer, to form a polyimide insulating layer.
4. The method according to claim 3 , wherein step (M) in which the formation of a through hole for ensuring conductivity between the metal layer and the upper circuit layer is performed between step (B) and step (C) or subsequent to step (C).
5. A method for manufacturing a double-sided flexible printed board, comprising the following steps of:
(A) forming a polyimide precursor layer on a metal layer;
(B) forming an upper circuit layer on the polyimide precursor layer by a semi-additive technique, leaving the polyimide precursor layer partially exposed at the upper circuit layer side; and
(C) after step (B), imidating the polyimide precursor layer to form a polyimide insulating layer.
6. The method according to claim 5 , wherein step (M) in which the formation of a through hole for ensuring conductivity between the metal layer and the upper circuit layer is performed between step (B) and step (C) or subsequent to step (C).