Magnetic recording medium and cartridge
US10964346B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 1, 2020 |
| Grant date | Mar 30, 2021 |
| Priority date | — |
| Expiry date | May 1, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/78
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording medium, includes a substrate; a magnetic layer; an underlayer between the substrate and the magnetic layer, the underlayer including a non-magnetic powder and a binding agent; and a back layer. In a case where wmax and wmin are respectively maximum and minimum of average values of width of the magnetic recording medium measured under four environments whose temperature and relative humidity are (10° C., 10%), (10° C., 80%), (29° C., 80%), and (45° C., 10%), respectively, wmax and wmin satisfy a relation of (wmax−wmin)/wmin≤400 [ppm]. The substrate includes polyester. A squareness ratio in a vertical direction of the magnetic medium is 65% or more, and an average thickness of the magnetic recording medium is 5.6 μm or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.