Printex 25 Domestic furnace black Degussa Extenders / Fillers >> Carbon black Pigments >> Carbon Black SEALANT Printex 25 Domestic Furnace Black UV stabilization Used as a pigment in caulks for interior and exterior applications and in expansion joints. Domestic furnace black. Used as a pigment in caulks for interior and exterior applications and in expansion joints. Provides UV stabilization.