Master carrier for magnetic transfer
View Patent ↗A master carrier for magnetic transfer having a data region and a servo pattern region that has a pattern of fine projections arrayed in the track direction thereof in accordance with the preformat signal information to be transferred onto an in-plane magnetic recording medium is disclosed. The data region has a projection formed of a material such as carbon-based material that differs from the material of the servo pattern region.
1. A master carrier for magnetic transfer, comprising:
a data region and
a servo pattern region that has a pattern comprising a first projection and unfilled depressions between projections, at least said first projection consisting of a first material comprising a soft magnetic material and being allayed in a track direction of said master carrier in accordance with a preformat signal information to be transferred to an in-plane magnetic recording medium,
wherein said data region is partly filled by a second projection consisting of a second material comprising a non-magnetic material, and said second material is different from said first material.
2. The master carrier for magnetic transfer as claimed in claim 1 , wherein said second material comprises a carbon based material or a chromium based material.
3. The master carrier for magnetic transfer as claimed in claim 1 , wherein said second projection is formed by a deposition.
4. The master carrier for magnetic transfer as claimed in claim 1 , said second projection substantially has same height as that of said first projection.
5. The master carrier for magnetic transfer as claimed in claim 1 , wherein said second projection is 0.6 to 1.4 times as high as said first projection.
6. The master carrier for magnetic transfer as claimed in claim 1 , wherein said second projection is 0.8 to 1.2 times as high as said first projection.
7. The master carrier for magnetic transfer as claimed in claim 1 , which has an interval along a border line between said servo pattern region and said data region disposed adjacent to each other.
8. A process of producing a preformatted magnetic recording medium, which comprises the steps of:
preparing a magnetic transfer master,
preparing a slave medium comprising a non-magnetic support having a magnetic recording layer thereon,
initially magnetizing said magnetic recording layer of said slave medium to a predetermined direction,
bringing a surface of said master medium into intimate contact with said magnetic recording layer of said slave medium at a predetermined pressure to form a conjoined body, and
applying a transfer magnetic field to said conjoined body in a direction opposite to said predetermined direction, thereby obtaining said magnetic recording medium having said recorded data,
wherein said magnetic transfer master comprises a data region and a servo pattern region that has a pattern comprising a first projection and unfilled depressions between projections, at least said first projection consisting of a first material comprising a soft magnetic material and being allayed in a track direction of said master carrier in accordance with a preformat signal information to be transferred to an in-plane magnetic recording medium,
wherein said data region is partly filled by a second projection consisting of a second material comprising a non-magnetic material, and said second material is different from said first material.
9. The process of producing a preformatted magnetic recording medium according to claim 8 , wherein said second material comprises a carbon based material or a chromium based material.
10. The process of producing a preformatted magnetic recording medium according to claim 8 , wherein said second projection is formed by a deposition.
11. The process of producing a preformatted magnetic recording medium according to claim 8 , said second projection substantially has same height as that of said first projection.
12. The process of producing a preformatted magnetic recording medium according to claim 8 , wherein said second projection is 0.6 to 1.4 times as high as said first projection.
13. The process of producing a preformatted magnetic recording medium according to claim 8 , wherein said second projection is 0.8 to 1.2 times as high as said first projection.
14. The process of producing a preformatted magnetic recording medium according to claim 8 , wherein said magnetic transfer master has an interval along a border line between said servo pattern region and said data region disposed adjacent to each other.