COMPOSITIONS AND METHODS FOR PROVIDING ANISOTROPIC CONDUCTIVE PATHWAYS AND BONDS BETWEEN TWO SETS OF CONDUCTORS

摘要

The invention provides a composition (3) comprising: (i) a ferrofluid comprising a colloidal suspension (4) of ferromagnetic particles in a non-magnetic carrier liquid, and (ii) a plurality of electrically-conductive particles (5) having substantially uniform sizes and shapes, dispersed in the ferrofluid. Various types of substantially non-magnetic electrically-conductive particles (5) are described. Application of a substantially uniform magnetic field by magnet means (8) to the composition (3) causes the electrically-conductive particles (5) to form a regular pattern (9). The composition is used for providing anisotropic conductive pathways (9a, 9b) between two sets of conductors (2a, 2b; 7a, 7b) in the electronics industry. The composition may be a curable adhesive composition which bonds the conductors. Alternatively or in addition the electrically-conductive particles may have a latent adhesive property e.g. the particles may be solder particles. The ferrofluid may be a colloidal suspension of ferromagnetic particles in a liquid monomer.