Master information carrier for magnetic transfer
AssigneeFuji Photo Film Co., Ltd.
InventorsRyuji Sugita, Masakazu Nishikawa, Tadashi Yasunaga
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Abstract
A master information carrier for magnetic transfer includes a substrate having an irregularity pattern representing information to be transferred to a slave medium and a magnetic layer formed on the irregularity pattern on the substrate. The depth d of the recessed portions of the irregularity pattern and the thickness t of the magnetic layer formed on the recessed portions satisfy formula −0.004≦(t−d)/d≦0.1. At the same time, the magnetic layer formed on the protruding portion of the irregularity pattern and the magnetic layer formed on the recessed portions of the irregularity pattern are connected with each other.
Claims11
A master information carrier for magnetic transfer comprising a substrate having an irregularity pattern representing information to be transferred to a slave medium and a magnetic layer formed on the irregularity pattern on the substrate, wherein the improvement comprises that
- formula −0.0004≦(t−d)/d≦0.1 is satisfied where d represents the depth of the recessed portions of the irregularity pattern and t represents the thickness of the magnetic layer formed on the recess portions, the magnetic layer formed on the protruding portions of the irregularity pattern and the magnetic layer formed on the recessed portions of the irregularity pattern are connected with each other;
- and wherein the formula 0.01δ/t≦0.5 is satisfied and wherein further, δ represents the thickness of the magnetic layer of the side wall connecting the magnetic layer on the protruding portions and the magnetic layer on the recessed portions.
A master information carrier comprising:
- a substrate with an irregularity pattern disposed thereon wherein the irregularity pattern comprises alternating recessed and protrusion portions;
- and
- a magnetic layer disposed on top of the irregularity pattern,
- wherein the depth of the recessed portions of the irregularity pattern is represented by d and a thickness of the magnetic layer formed on the recessed portions is represented by t and −0.004≦(t−d)/d≦0.1;
- and wherein said magnetic layer comprises a connecting portion connecting the magnetic layer formed on the protruding portions of the irregularity pattern and the magnetic layer formed on the recessed portions of the irregularity pattern and wherein further, 0.01≦δ/t≦0.5, wherein δ represents the thickness of the connecting portion.
Dependencies are inferred from the claim text.