Pre-coated coiled material epoxy resin type back paint

The invention discloses a high-processability epoxy back paint which can be used in the field of pre-coated coiled materials. The invention aims to provide the pre-coated coil epoxy resin back paint with high solid content, high processability, low VOC (volatile organic compound) and high mechanical property. The coating comprises the following components in parts by mass: 15-20 parts of modified epoxy resin A, 50-65 parts of modified epoxy resin B, 0.2-1 part of a dispersing agent, 5-15 parts of a filler, 0.1-10 parts of a pigment, 0.4-6 parts of a core-shell nano material, 1-5 parts of a solvent, 0.5-1 part of an anti-settling thixotropic agent, 0.5-2.0 parts of an adhesion promoter and 6-10 parts of a curing agent, wherein the sum of the parts by weight of the components is 100. And after the paint is prepared, the content of non-volatile matters is more than or equal to 80%, the viscosity is 80-125s (Tu-4 cup, 25 DEG C), the VOC is less than 300g/L, and the settleability grade is more than or equal to gra