Patents by Inventor John W. Mackay

John W. Mackay has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Smooth, low-friction magnetic recording medium
    Patent number: 4693930
    Abstract: 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 m.sup.2 /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.
    Type: Grant
    Filed: May 3, 1985
    Date of Patent: September 15, 1987
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Richard J. Kuo, John W. Mackay, Rick L. Van Buren