Production of electrical circuit boards

摘要

A method of forming a conductive path (11) of an electrical circuit board (1) comprises applying an adhesive (7) to a substrate (3) and applying a conductive ink (25) over the adhesive (7) in a pattern corresponding to the desired conductive path (11). A photoimageable layer (9) can be applied over the adhesive (7) or substrate and subjected to a photoimaging and developing process. This forms a track (13) in the photoimageable layer (9), corresponding to the desired conductive path (11). The conductive ink (25) is introduced into the track (13) prior to heating. The heating affects curing of the adhesive (7) and bonding of the conductive ink (25) to the adhesive layer (7) simultaneously with reflow or sintering of a metallic component (27) of the ink. The ink (25) comprises a metallic component (27) and a flux but is substantially free of any resin or any reactive monomer or polymer.