Lubricant for magnetic recording material, e.g. video-tape

摘要

A lubricant (I) consists of a sorbitan ester cpd. with a structure in which at least one of the OH gps. of 1,5-sorbitan is attached via an ester link to a perfluoro-polyether with a terminal COOH gp. and at least one other OH gp. is attached via an ester link to a hydrocarbon with a terminal COOH gp. Also claimed is a magnetic recording medium comprising a non-magnetic substrate coated with at least one magnetic recording layer, with lubricant (I) on the surface of the recording layer.