SMOOTH, LOW-FRICTION MAGNETIC RECORDING MEDIUM

摘要

Flexible magnetic recording media such as videotapes based on ferromagnetic oxide particles can provide high carrier-to-noise ratios previously available only with metal powder tapes when the recording layer has a high loading (at least 74% by weight) of oxide particles which have a high surface area (at least 40 m2/g) and includes free monobasic fatty acid comprising more than 1.5% by weight of the ferromagnetic oxide particles. The free fatty acid provides a coefficient of friction not exceeding 0.3. A preferred monobasic fatty acid is myristic acid. By incorporating into the binder a lubricant-adsorption inhibitor such as citric acid, a greater proportion of the fatty acid remains free.