Self-adhesive compositions with improved tracking resistance for coating metal substrates

摘要

An auto-adhesive composition for coating metal substrate based on thermoplastic and/or thermosetting resins comprises at least one uncoated calcium carbonate precipitate, in powder form, with specific surface area of 7-12 m<2>g<-1> and specific apparent mass in suspension of 130-180, preferably 150 gl<-1>. Also claimed are (1) preparation of the composition by mixing in molten state then crushing and/or mixing different constituents in dry state; (2) use of calcium carbonate precipitate as tread-resistance additive; and (3) a material comprising a metallic substrate with coating of above composition produced by melting components. Preferably the composition is based on polyamide, preferably polyamide PA-11 and/or PA-12; and it also contains additives such as fillers, pigments and antioxidants.