Method for preparing silicon dioxide coated type aluminum pigment

The invention discloses a method for preparing a silicon dioxide coated type aluminum pigment. The method comprises the following steps: uniformly dispersing a clean aluminum pigment of which impurity oil is removed into an alcohol solvent, adding water, stirring uniformly, and adding a polymerization inhibitor so as to obtain an aluminum pigment mixed liquid; uniformly mixing tetraethyl orthosilicate, the alcohol solvent and water, adding an acid pH conditioning agent to adjust the pH value to 5.5-6.5, hydrolyzing tetraethyl orthosilicate so as to obtain a first solution; adding an alkali pH conditioning agent into the alcohol solvent to adjust the pH value to 8-9 so as to obtain a second solution; and dropping the first solution and the second solution into the aluminum pigment mixed liquid, performing a reaction, and drying after the treatment, thereby obtaining the silicon dioxide coated type aluminum pigment. On one hand, the polymerization inhibitor is added, and on the other hand, tetraethyl orthosilicate is hydrolyzed under an acid condition, so that under the action of the polymerization inhibitor and tetraethyl orthosilicate, the silicon dioxide coated type aluminum pigment is dense in structure, complete in coating, small in particle size, uniform in distribution and free of seeding or caking phenomenon.