Patent · US Expired

Method of a making magnetic recording medium

US4847109A · kind A · utility

4Cited by
1References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 10, 1988
Grant dateJul 11, 1989
Priority date
Expiry dateMay 10, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/85
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of and an apparatus for making a magnetic recording tape, which is free from wrinkles formed thereon, by the use of a vapor deposition technique. A length of tape reeled on a supply reel is taken up by a take-up reel after having passed through a deposition station where it is movably turned around a cylindrical drum. In one aspect, the difference in tension between two different portions of the tape moving between the drum and the take-up reel and on respective sides of a tensioning roll forming a part of at least one tension control mechanism is adjusted to a value not greater than 10N/mm.sup.2. In another aspect, a charge eraser is employed and installed in the vicinity of the drum for removing an electrostatic charge built up in the tape being moved from the drum onto the take-up reel. In a further aspect, the cylindrical drum is used having its outer peripheral surface roughened to a ten-point average surface roughness of not smaller than 0.1 .mu.m.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.