Flexible magnetic recording medium
AssigneeFuji Photo Film Co., Ltd.
InventorsHitoshi Noguchi, Kazuhiro Niitsuma
Life of this patent
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Abstract
A flexible magnetic recording medium to which data is transferred by being brought into intimate contact with a master carrier which has a land/groove pattern corresponding to the data and also has a surface whose Moh's hardness is 6 to 10. The magnetic recording medium includes a substrate, a non-magnetic layer, and a magnetic layer. The non-magnetic layer and the magnetic layer are coated on the substrate in the recited order. The magnetic layer contains an abrasive comprising diamond particles whose average particle size is 0.03 to 0.5 μm. The diamond particle content of the abrasive is in a range of 0.1 to 5 wt % of ferromagnetic powder contained in the magnetic layer.
Claims14
A flexible magnetic recording medium to which data is transferred by being brought into intimate contact with a master carrier which has a land/groove pattern corresponding to said data and also has a surface whose Moh's hardness is 6 to 10, said magnetic recording medium comprising:
- a substrate;
- and
- a non-magnetic layer and a magnetic layer coated on said substrate in the recited order;
- wherein said magnetic layer contains an abrasive comprising diamond particles whose average particle size is 0.03 to 0.5 μm, and the diamond particle content of said abrasive is in a range of 0.1 to 5 wt % of ferromagnetic powder contained in said magnetic layer.
A flexible magnetic recording medium to which data is transferred by being brought into intimate contact with a master carrier which has a magnetic pattern corresponding to said data, said magnetic recording medium comprising:
- a non-magnetic substrate;
- and
- a non-magnetic layer and a magnetic layer formed on said substrate in the recited order;
- wherein said magnetic layer includes polyurethane resin which contains in a range of 0.05 to 0.7 meq/g at least one kind of polar group selected from the group consisting of —SO3M, —OSO3M, —P═O(OM)2, —O—P═O(OM)2, and —COOH (where M represents a hydrogen atom, alkali metals, or an ammonium salt);
- and wherein the polyurethane resin content is 60 wt % or greater of the quantity of all resins in said magnetic layer.
A flexible magnetic recording medium to which data is transferred by being brought into intimate contact with a master carrier which has a land/groove pattern corresponding to said data, said magnetic recording medium comprising:
- a non-magnetic substrate;
- and
- a non-magnetic layer and a magnetic layer coated on said substrate in the recited order;
- wherein a relationship between the Moh's hardness (X) of the surface of said master carrier and the Knoop hardness (Y kg/mm2) of the surface of said magnetic recording medium is represented as 1≦Y/X≦7.
A flexible magnetic recording medium to which data is magnetically transferred by being brought into intimate contact with a master carrier which has a land/groove pattern corresponding to said data, said magnetic recording medium comprising:
- a substrate;
- and
- a non-magnetic layer and a magnetic layer coated on said substrate in the recited order;
- wherein a first coating solution for forming said non-magnetic layer contains a first lubricant in a range of 1 to 20 wt % of non-magnetic powder contained in said non-magnetic layer;
- wherein a second coating solution for forming said magnetic layer contains a second lubricant which is ¼ or less of said first lubricant in quantity;
- and wherein said first and second lubricants are liquids at a temperature at which said magnetic transfer is performed.
A method of fabricating a flexible magnetic recording medium, comprising the steps of:
- stacking a non-magnetic layer which contains in a range of 1 to 20 wt % of non-magnetic powder a first coating solution being a liquid at a temperature at which magnetic transfer is performed, and a magnetic layer which contains a second coating solution being ¼ or less of said first lubricant in quantity and also being a liquid at said temperature, on a substrate in the recited order;
- brining a master carrier, which has a land/groove pattern corresponding to data to be transferred, into intimate contact with said stacked body to transfer said data to said stacked body;
- and
- treating said stacked body with heat.
Dependencies are inferred from the claim text.