Patent · US Expired

Magnetic tape

US5316823A · kind A · utility

9Cited by
6References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 12, 1992
Grant dateMay 31, 1994
Priority date
Expiry dateFeb 12, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31786
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic tape for audio cassettes wherein a magnetic layer is provided on base film characterized in that the a base film, is biaxially oriented polyethylene-2,6-naphthalate film having a Young's modulus in the longitudinal direction of 850 Kg/mm.sup.2 or more, a Young's modulus in the transverse direction of 550 Kg/mm.sup.2 or more a surface roughness Ra in the range of 0.015 to 0.040 .mu.m, and a thermal shrinkage rate in the longitudinal direction of 0.3% or less in a case where it was held at a temperature of 100.degree. C. for 1 hour. A magnetic tape for audio cassettes is provided which is capable of long-time recording and wherein deterioration of magnetic characteristics does not easily occur in use, storage and the like at a high temperature, for example in the open during summer or in cars, compared to conventional ones.

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