▎ 摘　　要

NOVELTY - Electromagnetic wave shielding coating method comprises surface treatment of surface-treating contaminants including rust, dust, and oil on the surface of a steel material using a surface treatment device, applying water-soluble urethane-based rust-preventing coating for applying a water-soluble acrylic resin-based composition consisting of co-solvent, coloring pigment or filler is graphene-coated, and mixing graphene oxide with an organic acidic material to prepare a solution in which graphene oxide is dispersed, adding and mixing colored pigment or a filler in the solution in which the graphene oxide is dispersed, adding a reducing agent, partially reducing at room temperature, and ending reduction by irradiating microwaves and separating the reduced graphene oxide-coated colored pigment or filler. USE - The method is useful for steel materials. ADVANTAGE - The method improves electromagnetic wave shielding performance. DETAILED DESCRIPTION - Electromagnetic wave shielding coating method comprises surface treatment of surface-treating contaminants including rust, dust, and oil on the surface of a steel material using a surface treatment device, where water-soluble epoxy resin is 20-45 wt.% bisphenol A liquid epoxy resin, 15-40 wt.% water, 0.1-1 wt.% dispersant, 0.1-1 wt.% antifoaming agent, 0.1-1 wt.% thickener, 10-30 wt.% coloring pigment, 10-30 wt.% filler, 1-15 wt.% corrosion inhibitor, 0.1-5 wt.% silane, 0.1-1 wt.% wetting agent, 200-350 g/eq epoxy equivalent, a subject having a viscosity of 500-1,500 cps at room temperature, 50-70 wt.% amine curing agent, 25-45 wt.% water, 0.1-1 wt.% antifoaming agent, curing agent consisting 0.1-4 wt.% thickener, subject: curing agent = 9, applying water-soluble epoxy-based rust-preventing paint coating step of applying a water-soluble epoxy resin mixed in a weight ratio of 1, 55-80 wt.% water acrylic urethane resin, 0.2-1 wt.% dispersant, 0.2-1 wt.% antifoaming agent, 0.5-1.5 wt.% thickener, 10-30 wt.% coloring pigment, 0.1-0.8 wt.% wetting agent, 0.1-4 wt.% silane, applying water-soluble urethane-based rust-preventing coating for applying a water-soluble acrylic resin-based composition consisting of 0.1-10 wt.% co-solvent, coloring pigment or filler is graphene-coated, and mixing graphene oxide with an organic acidic material to prepare a solution in which graphene oxide is dispersed, adding and mixing colored pigment or a filler in the solution in which the graphene oxide is dispersed, adding a reducing agent, partially reducing at room temperature, and ending reduction by irradiating microwaves and separating the reduced graphene oxide-coated colored pigment or filler.