there is disclosed a method for the imprinting and decorating rotomolded products . the method comprises the application to the interior surfaces of the mold of a viscous suspension of pigment in a preselected pattern . the suspension is applied to the mold surface in an oil carrier using a vegetable , animal or mineral oil that is inert under the molding conditions and that has a sufficient viscosity at the molding conditions to maintain the film on the mold surfaces . the pattern of the pigment suspension is applied by spraying , brushing , screen printing and the like and , after its application , the conventional rotomolding can be practiced . in this method , the powdered plastic , typically high density polyethylene , in powder form is charged to the mold , the mold is closed and placed in an oven heated to from 500 ° f . to about 800 ° f . while rotating the mold along two axes , to tumble the plastic powder against the heated side of the mold where the powder consolidates into an integral molded wall of a plastic shape . the invention provides a very high line or character definition preferably using finely subdivided pigments .