Question: What product is bitumen used in manufacturing as a sealant?
Sentence: Asphalt/bitumen is used to make Japan black, a lacquer known especially for its use on iron and steel, and it is also used in paint and marker inks by some graffiti supply companies to increase the weather resistance and permanence of the paint or ink, and to make the color much darker.[citation needed] Asphalt/bitumen is also used to seal some alkaline batteries during the manufacturing process.
Answer in sentence: yes