Finally, the processed TiO2-PP-granulate was transferred to the extruder/spooler-device for the manufacturing of the 3D-printing filament. The optical filament thickness sensor of the device allowed for almost fully automated and monitored manufacturing. Only the granulate had to be refilled manually over time. TiO2-PP-filaments with TiO2 loadings up to 20 wt% could be manufactured in every amount needed for the 3D-printing part. By default, 100 g of filament were produced in this way for different catalyst loadings. Since 20 wt% filament caused frequent clogging, which was attributed to the high catalyst loading, 15 wt% filaments were manufactured as standard.