A method of clearing photoresist on a wafer edge, including the following steps. The pigment comprises a platy substrate coated with SnO2 andor SnO2 hydrates and Fe3O4 with an optional coating of metal oxides such as SiO2, TiO2, ZrO2 and ZnO2. It is possible to solve the state of competing for the bus access right between both buses. The carrier plate, stripping blade and scraping blade also include apertures through which a fastening means secures these respective components but which nevertheless selectively permits movement of the carrier plate along the stripping blade.