Patent · US Expired

Biaxially oriented polyester film for magnetic recording media

US5252388A · kind A · utility

19Cited by
3References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 13, 1991
Grant dateOct 12, 1993
Priority date
Expiry dateDec 13, 2011

Classification

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

Abstract

A biaxially oriented polyester film for magnetic recording media, which comprises: PA1 (A) 0.05 to 1.0% by weight of .theta.-aluminum oxide or mixed (.alpha.+.gamma.) aluminum oxide having an average particle diameter in the range of from 0.02 to 0.3 .mu.m and a specific surface area in the range of from 50 to 120 m.sup.2 /g, and PA1 (B) 0.01 to 1.5% by weight of inert particles having an average particle diameter which is in the range of from 0.1 to 1.5 .mu.m and greater than the average particle diameter of the aluminum oxide.

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