PURPOSE: To enable cutting without burring at the cut end without need for providing additionally a protective layer to the cut surface with a method for cutting a magnetic recording medium of a thin metallic film type by laser light by limiting the Young's modulus of said medium.
CONSTITUTION: A magnetic recording medium which is formed successively with a ferromagnetic thin metallic film and a protective film on a non-magnetic high polymer base and has ≤800kg/mm2 Young's modulus at 1% elongation is cut by using laser light. Since the temp. of the cut surface rises to several hundred degrees according to the above-mentioned method, a dense oxidized film is formed on the cut surface (metallic film) and this film prevents intrusion of oxygen and moisture. There is therefore no need for providing additionally the protective layer on the cut surface. The cut end is clean and burr-free.
KIKUKAWA SHIYOUZOU
ISHIGURO SHIYUU
| JPS51110307A | 1976-09-29 | |||
| JPS5436705A | 1979-03-17 |
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