Antimony is mainly used as an alloying component for hardening other soft metals such as lead, copper, tin or zinc. Very pure antimony is also used in semiconductors. Another area of application is the production of flame retardants. Paints, textiles and plastics with flame-resistant or flame-retardant properties are important for the automotive and electrical engineering industries, among others. In oxide form, the semi-metal is used as a catalyst for the production of PET plastic.