CONTEXTO: Back coating with a carbon type material is also applied to improve durability and runnability.
back coating : In magnetic recording tape, a thin coating applied to the non-oxide or back surface of the tape to reduce slippage between tape layers, prevent accumulation of static charge, and to minimize curling or wrinkling.
Em espanhol é capa posterior mas em PT-PT não tenho a certeza...
revestimento posterior?
The translation workplace 
