| 摘要 |
PROBLEM TO BE SOLVED: To increase the number of a magnetic duplication cycle by composing a flexible magnetic recording medium so that it is hard to generate corrosion on a master support surface for magnetic duplication. SOLUTION: The polyurethane resin containing at least a kind of polar group in a range from 0.05 to 0.7 meq/g is made to contain at 60% by weight or more with respect to the total amount of resin in a magnetic layer into the magnetic layer of the flexible magnetic recording medium which has a coating layer including the magnetic layer and a non-magnetic layer. The polar group is selected from -SO<SB>3</SB>M, -OSO<SB>3</SB>M, -P=O(OM)<SB>2</SB>, -O-P=O(OM)<SB>2</SB>and -COOM (M expresses hydrogen atom, alkali metal, or ammonium salt). COPYRIGHT: (C)2003,JPO
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