▎ 摘　　要

NOVELTY - A conductive silver paste preparation method involves utilizing raw materials comprising spherical silver powder, flake silver powder, graphene, epoxy modified polyester resin (organic carrier), organic solvent, aluminum nitride, polyether modified silicone (defoaming agent), polyacrylate (leveling agent) and diaminodiphenylmethane or diaminodiphenyl sulfone (curing agent) followed by adding the epoxy modified polyester resin to the organic solvent, heating, uniformly stirring, until the resin is completely dissolved, stirring in constant temperature water bath, cooling to obtain product with viscosity of 8000-10000 cps, adding defoaming agent, leveling agent, curing agent and aluminum nitride, uniformly stirring, adding spherical silver powder, flake silver powder and graphene in batches, adding obtained product to high speed disperser, obtaining primary silver paste, adding to three roll mill, milling, stirring, heating, rapidly filtering using polyester mesh. USE - Method for preparing conductive silver paste that is utilized for printed circuit. ADVANTAGE - The method enables preparing conductive silver paste with excellent electrical conductivity and better adhesion and bending resistance. DETAILED DESCRIPTION - A conductive silver paste preparation method involves utilizing raw materials comprising 10-15 pts. wt. spherical silver powder, 20-30 pts. wt. flake silver powder, 7-10 pts. wt. graphene, 8-12 pts. wt. epoxy modified polyester resin (organic carrier), 10-15 pts. wt. organic solvent with boiling point of 120-180 degrees C, 1-2 pts. wt. aluminum nitride, 0.1-1 pts. wt. polyether modified silicone (defoaming agent), 0.1-1 pts. wt. polyacrylate (leveling agent) and 0.5-1.2 pts. wt. diaminodiphenylmethane or diaminodiphenyl sulfone (curing agent), adding the epoxy modified polyester resin to the organic solvent, heating at 60-90 degrees C, uniformly stirring, until the resin is completely dissolved, stirring in constant temperature water bath at 90 degrees C for 4-8 hours, cooling to obtain product with viscosity of 8000-10000 cps, adding defoaming agent, leveling agent, curing agent and aluminum nitride, uniformly stirring, adding spherical silver powder, flake silver powder and graphene in batches, adding obtained product to high speed disperser, obtaining primary silver paste, adding to three roll mill, milling at speed of 50-55 rotations per minute, till fineness of less than 5 mu m, stirring, heating, rapidly filtering using polyester mesh, where the spherical silver powder has particle diameter of 0.5-1.5 mu m and tap density of 3-5 g/cm3, the flake silver powder has particle diameter of 1-2 mu m and tap density of 3-5 g/cm3, the graphene has particle size of 6-8 nm, the organic solvent is cyclohexanone or propylene glycol methyl ether acetate, the epoxy modified polyester resin has average molecular weight of 50000-80000 and the aluminum nitride is spherical and average particle size of 50 nm-1 mu m. An INDEPENDENT CLAIM is also included for a conductive silver paste prepared by the method.