Light-heat dual curing anisotropic conductive adhesive, anisotropic conductive film and preparation methods thereof

A preparation method of an anisotropic conductive adhesive film comprising a plastic film base material and a conductive adhesive layer produced by coating a light-heat dual curing anisotropic conductive adhesive on the plastic film base material and curing the coating with ultraviolet light to form said conductive adhesive layer;

• said light-heat dual curing anisotropic conductive adhesive consisting of light curing active monomer 15.0-18.0%, light-curing resin 4.5-12.5%, thermosetting resin 20.0-25.0%, elastomer 5.0-10.0%, plasticizer 3.0-6.0%, insulating nanoparticles 8.0-15.0%, conductive particles 4.0-18.0%, light curing agent 3.0-5.0%, latent heat curing agent 12.0-16.0%, coupling agent 0.5-1.0%, leveling agent 0.5-1.5% and antioxidant 0.5-1.0%, wherein the above-mentioned components are calculated according to weight percentage, and wherein the conductive adhesive film further comprises a protective film that covers the conductive adhesive layer, the method comprising the following steps:
• 1) putting a solid-state light-curing resin, a solid-state thermosetting resin and a solid-state elastomer in a dispersing mixer, then heating them to temperature between 130° C. to 150° C. to melt and form a mixture,
• 2) adding a liquid-state light curing active monomer and plasticizer to the above-mentioned mixture that has been cooled to the temperature below 80° C.;
• 3) adding separately the leveling agent, antioxidant and insulating nanoparticles to the mixture;
• 4) adding conductive particles to the mixture;
• 5) adding a light curing agent, latent heat curing agent and coupling agent to the mixture, so that a light-heat dual curing anisotropic conductive adhesive is produced;
• 6) coating the conductive adhesive on a plastic film base material with a coating machine thereby forming a semi-finished product;
• 7) curing and drying the semi-finished product with a UV curing machine to form a cured conductive adhesive layer;
• 8) covering the cured conductive adhesive layer with a protective film, so that an anisotropic conductive adhesive film is produced;
• 9) cutting with a slitting machine through the anisotropic conductive adhesive layer without cutting the plastic film base material;
• and then rolling the anisotropic conductive adhesive film,
• wherein steps 1 to 7 are performed without using a solvent.