Cathodic water-soluble electrophoretic paint emulsion and preparation method thereof

The invention provides a cathodic water-soluble electrophoretic paint emulsion and a preparation method thereof. The emulsion comprises the following raw materials in percentage by mass: 25-40% of epoxy resin, 20-30% of curing agent, 2-4% of aliphatic amine, 1-2% of nontoxic drier and 20-40% of deionized water. The preparation method comprises the steps of a, adding epoxy resin into a clean and dry normal pressure kettle, adding deionized water, starting stirring for 20 minutes, meanwhile, adding polyurethane having the same mass as the epoxy resin and purified water having the same mass as the polyurethane into another normal pressure kettle, heating to 155 DEG C, starting stirring for 20 minutes, then cooling to 85 DEG C, measuring the viscosity of the materials in the two normal pressure kettles after stirring, and continuously stirring if the viscosity is not qualified till qualified viscosity is obtained. The preparation method disclosed by the invention is relatively reasonable in proportioning and relatively low in cost; the product has a relatively flat surface and is safe, environment-friendly and good in corrosion resistance; the reaction velocity is improved; and the conversion rate is improved.