The commonly used paints on the bottom of the ship are divided into two types: anti-rust paint and anti-fouling paint: Anti-rust paint: (1) Asphalt antirust paint, chlorinated rubber antirust paint, ethylene aluminum powder/ethylene asphalt antirust paint, tar epoxy antirust paint, modified epoxy antirust paint (2) Antifouling paint:  Asphalt antifouling paint (validity 12-18 months), Chlorinated rubber antifouling paint (valid for 24-30 months), Organotin polymer (valid for 36-60 months), TBT-free self-polishing antifouling paint (validity 36-60 months), Silicone or fluoropolymer antifouling paint (valid for 60 months).