powder coating material
Patent No. U.S. 6,547,869 B2
Merck has been granted a patent for a process for preparing a powder coating material. It is comprised of processing as a melt in an extruder, at least one binder and at least one pigment, and optionally, at least one filler, additive and/or cross linker, and premixing, to give a homogeneous mixture and grinding, after cooling, to a finished powder. At least part of the pigment comprises a platelet-shaped, surface-modified effect pigment that has been coated with a low molecular mass polyethylene or polypropylene.