Magnetic recording medium
US4152485A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 27, 1978 |
| Grant date | May 1, 1979 |
| Priority date | — |
| Expiry date | Jul 27, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31786
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording medium having a high ratio of the residual magnetization (Br) to the saturation magnetization (Bm) and decreased voids, which has a magnetizable layer of magnetic particles which are dispersed in a binder: a polyester or polyurethane having a metal sulfonate group of 10 to 1,000 equivalents/10.sup.6 g of the polymer, preferably a polyester having a reduced viscosity of 0.2 or more and having a metal sulfonate group of 20 to 300 equivalents/10.sup.6 g of the polyester; a polyester having a reduced viscosity of less than 0.2 and having a metal sulfonate group of 20 to 500 equivalents/10.sup.6 g of the polyester; or a polyurethane having a metal sulfonate group of 20 to 400 equivalents/10.sup.6 g of the polyurethane. Said magnetic recording medium is particularly suitable for an electronic computer tape and video tape.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.