Films and coatings having anisotropic conductive pathways therein

• Main Authors: MCARDLE, CIARAN BERNARD, BURKE, JOSEPH
• Format: Patent
• Language: English; French; German
• Published: 11.04.2001
• Edition: 7
• Subjects: BASIC ELECTRIC ELEMENTS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; CURRENT COLLECTORS; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INDUCTANCES; LINE CONNECTORS; MAGNETS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; PRINTED CIRCUITS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS

An anisotropically-conductive film or a substrate having a surface coated with an anisotropically-conductive coating, said film or coating being formed by solidifying a composition comprising (i) a solidifiable ferrofluid composition, the ferrofluid comprising a colloidal suspension of ferromagnetic particles in a non-magnetic carrier, and (ii) a plurality of electrically-conductive particles, dispersed in the ferrofluid, the electrically-conductive particles having been arrayed in a non-random pattern by application of a substantially uniform magnetic field to the composition in a liquid state and having been locked in position by solidification of the composition. The composition is solidified in an A-stage, usually involving a primary cure. In end-use application of the film or coating, the composition usually undergoes a B-stage or secondary cure. The film or coated substrate is an article of manufacture for bonding conductors in the electronics industry.