GB759486A - Improvements in or relating to magnetic recording media - Google Patents

Abstract

759,486. Magnetic structures. THERMIONIC PRODUCTS, Ltd. Jan. 22, 1954 [Jan. 29, 1953], No. 2613/53. Class 38 (2). [Also in Group VIII] A method of importing a highly glazed operative surface to a magnetic recording medium in the form of a coating of magnetic particles in a binder anchored to a flexible backing, e.g. of paper, consists in heating a portion of an optically smooth surface of a continuously moving member applying the medium under pressure against the heated portion of the optically smooth surface and subsequently stripping the medium from the surface at a point displaced from the heated portion in the direction of movement of the member. As shown in Fig. 1, the magnetic recording strips are fed from spools 13, 14 between optically smooth surfaces 1a, 2a of two endless bands driven by a motor 8 and are rewound on spools 15, 16. The bands pass between heated pressure units 9, 10 having cavities for hydraulic fluid supplied under pressure from a pipe 23 and electric, gas or steam heating means. In an alternative form the endless bands are replaced by a slowly driven drum with a smooth surface, an idler roller being spring urged to press the strip against the surface of the drum. A heating pipe within the drum is connected to a supply of steam, perforations in the pipe directing the steam on to the line of engagement with the idler roller. The lower part of the drum is cooled by water within the drum. A feed roller for supplying the magnetic recording strip is positioned above the drum together with a receptacle for a softening agent. The strip adheres to the surface of the drum and rotates therewith until after passing the water cooling zone, the sheet then being stripped by a take-up roller.