Magnetic recording medium
US4784907A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1986 |
| Grant date | Nov 15, 1988 |
| Priority date | — |
| Expiry date | Dec 22, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31935
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a magnetic recording medium such as a video tape comprising a nonmagnetic support and a magnetic recording layer provided on the support, said magnetic recording layer comprising a binder and a ferromagnetic powder dispersed therein, the improvement in which: PA1 the magnetic recording layer comprises a fatty acid ester lubricant and a lubricant other than the fatty acid ester lubricant; PA1 the binder is composed of a resin component comprising a resin containing a repeating unit which has a polar group and having a glass transition point of not lower than 50.degree. C., and a resin containing a repeating unit which has a polar group and having a glass transition point of lower than 50.degree. C; and PA1 at least one resin of the resins contains a repeating unit having a polar group such as --SO.sub.3 M, --OSO.sub.3 M or --PO(OM').sub.2, wherein M is hydrogen or an alkali metal atom, and M' is hydrogen, an alkali metal atom or a lower hydrocarbon group.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.