Magnetic recording medium and cartridge
AssigneeSony Group Corporation
InventorsMinoru Yamaga, Tooru Sato
Life of this patent
Estimating the term…
Abstract
Provided are a magnetic recording medium and a magnetic recording cartridge. An average thickness of the magnetic recording medium tT is tT≤5.3 μm, a ratio (A2/A1) of an average creep slope A2 at a temperature of 32° C. and a humidity of 80% RH to an average creep slope A1 at a temperature of 32° C. and a humidity of 20% RH is 1.440 or less, and a ratio (Tan δ2/Tan δ1) of an average Tan δ2 at a temperature of 32° C. and a humidity of 80% RH to an average Tan δ1 at a temperature of 32° C. and a humidity of 20% RH is less than 1.2100. The magnetic recording cartridge includes the magnetic recording medium, a memory and a case that accommodates the magnetic recording medium and the memory.
Claims27
A magnetic recording medium comprising:
- a magnetic layer and a substrate,
- an average thickness of the magnetic recording medium tT is tT≤5.3 μm,
- a ratio (A2/A1) of an average creep slope A2 at a temperature of 32° C. and a humidity of 80% RH to an average creep slope A1 at a temperature of 32° C. and a humidity of 20% RH is 1.440 or less, and
- a ratio (Tan δ2/Tan δ1) of an average Tan δ2 at a temperature of 32° C. and a humidity of 80% RH to an average Tan δ1 at a temperature of 32° C. and a humidity of 20% RH is less than 1.2100,
- wherein an average width change amount ΔW of the magnetic recording medium with respect to a temperature change at a humidity of 80% RH is 160 nm/° C. or less,
- wherein the magnetic layer includes a plurality of magnetic particles including at least one of hexagonal ferrite, epsilon-type iron oxide, or Co-containing spinel ferrite, and
- wherein the substrate includes a polyester-based resin.
A magnetic recording cartridge comprising:
- a magnetic recording medium,
- a memory, and
- a case that accommodates the magnetic recording medium and the memory, wherein the magnetic recording medium includes:
- a magnetic layer and a substrate,
- an average thickness of the magnetic recording medium tT is tT≤5.3 μm,
- a ratio (A2/A1) of an average creep slope A2 at a temperature of 32° C. and a humidity of 80% RH to an average creep slope A1 at a temperature of 32° C. and a humidity of 20% RH is 1.440 or less, and
- a ratio (Tan δ2/Tan δ1) of an average Tan δ2 at a temperature of 32° C. and a humidity of 80% RH to an average Tan δ1 at a temperature of 32° C. and a humidity of 20% RH is less than 1.2100,
- wherein an average width change amount ΔW of the magnetic recording medium with respect to a temperature change at a humidity of 80% RH is 160 mm/° C. or less,
- wherein the magnetic layer includes a plurality of magnetic particles including at least one of hexagonal ferrite, epsilon-type iron oxide, or Co-containing spinel ferrite, and
- wherein the substrate includes a polyester-based resin.
Dependencies are inferred from the claim text.