Method of making a magnetic recording member
Abstract
Abstract A METHOD FOR PRODUCING A MAGNETIC RECORDING MEMBER HAVING A FILM OF MAGNETIC MATERIAL WITH A HIGHLY FINISHED SURFACE ON A BACKING LAYER IS DISCLOSED. THE METHOD INCLUDES THE STEPS OF PREPARING A GLASS DISC SUCH THAT THE DISC SURFACE IS OF NEAR OPTICAL FLATNESS, DEPOSITING A FILM OF MAGNETIC MATERIAL ON THE DISC, BONDING A BACKING LAYER TO THE FILM AND STRIPPING THE GLASS DISC FROM THE FILM TO REVEAL A HIGHLY FINISHED SURFACE ON THE FILM OF MAGNETIC MATERIAL, THE FILM BEING BONDED TO THE BACKING LAYER. A TWOSIDED MAGNETIC RECORDING MEMBER MAY BE PRODUCED BY PLACING TWO THREE-LAYER STRUCTURES BACK TO BACK AND STRIPPING BOTH GLASS DISCS TO REVEAL TWO HIGHLY FINISHED MAGNETIC FILMS.
Inventors
- 👤 Sidney Ties
Bibliographic Details
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