International Business Machines Corporation

Donald Gini

Dean B Stockton

Ronald A Merten

Alex Simonetti

Theodore L Larson

A coating head for use in strip-coating paper-card material with water-based, thixotropic magnetic recording ink, in order to produce disposable magnetic recording media which is intended for one write operation, followed by only a few read operations. The head sits on the card and contains a quantity of ink at ambient pressure and temperature. As the head and card move relative one another, the ink is subjected to a shear force, and a bottom surface layer of the ink is drawn into a trailing wall of the head, which wall contains a metering orifice. This orifice is of gradually increasing cross-section. That is, the orifice's entrance area is smaller than is its exit area. In this manner, the ink is subjected to a coating interface through which the ink experiences a reduction in hydrodynamic pressure, and a decrease in velocity, as the volume of the coating orifice increases. As a result, the viscosity of the ink increases as the ink progresses through the coating orifice.

Method and apparatus for coating magnetic recording media

Magnetic recording media highly loaded with magnetic oxide particles. This media possesses a very smooth surface finish, and in operation exhibits low media wear, as well as low wear of an associated transducing head. This media includes an internal lubricant tridecyl stearate; i.e. a linear, 31-carbon fatty acid ester molecule formed by the ester linking of 13-carbon tridecyl alcohol and 18-carbon stearic acid, the molecule having the composition ##STR1##

Growing community of inventors

Boulder, CO, United States of America

Donald Gini