DE2500546

In the prepn. of a flexible layered tape, the magnetic layer is prepd. from a dispersion of magnetisable particles in a soln. in an organic solvent of a polymeric binder. This dispersion is applied to one side of a flexible synthetic tape provided on the other side with an adhesive intermediate layer (Z) based on a vinylidenechloride copolymer, contg. 70% vinylidene chloride, and a back layer (R) containing polymer bound carbon black. A dispersion is prepd. of 15-30 wt. % carbon black and 2-8 wt. % of a de-lustering agent in a binder of 62-83 wt. % elastomeric, isocyanate gp. free polyesterurethane, an epoxide resin (ratio 4:1) and non volatile polyisocyanates. The latter are present in an excess of 100-400 equiv. % over the quantity of isocyanate groups needed for crosslinking of total reactive groups in the layer R. This dispersion of carbon black is applied to the layer Z which contains 1-15 wt. %, relative to solids content of the copolymer of Di-n-octyltin-bis (2-ethyl-hexyl thioglycolate) (1). Esp. useful for video tapes.