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US3751345A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of producing a magnetic storage medium

Assignee: Unisys Corp
•
Filing: 1971-07-09
•
Granted: 1973-08-07
•
Expires: 1991-07-09
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Abstract

Abstract A MAGNETIZABLE STORAGE MEMBER IS FORMED FROM A SUBSTRATE AND THIN LAYERS DEPOSITED ON THE SUBSTRATE. THE THIN LAYERS INCLUDE AN ELEMENT HAVING PROPERTIES OF INITIALLY BEING NON-MAGNETIC AND OF BECOMING MAGNETIZABLE WHEN SUBJECTED TO HEAT AT A PARTICULAR ELEVATED TEMPERATURE. A THIN CHEMICALY INERT LAYER IS DISPOSED BETWEEN THE THIN MAGNETIZABLE LAYERS. THE MAGNETIIZABLE LAYERS MAY BE NICKEL AND THE CHEMICALLY INERT LAYER MAY BE GOLD. THE MAGNETIZABLE STORAGE MEMBER IS PROVIDED WITH MAGNETIC PROPERTIES CORRESPONDING TO THOSE PROVIDED BY A STORAGE MEMBER HAVING IRON OXIDE LAYERS. A HARD, THIN, NON-MAGNETIC PROTECTIVE COATING MAY BE DISPOSED ON THE STORAGE MEMBER AND MAY BE MADE FROM A SILICONE. THE STORAGE MEMBER IS FORMED FROM THE DIFFERENT LAYERS DICUSSED ABOVE AND IS THEN BAKED AT THE PARTICULAR ELEVATED TEMPERATURES TO MAKE THE STORAGE MEMBER MAGNETIZABLE.

Inventors

  • 👤 G Wilhelm
  • 👤 S Nagy
  • 👤 M Hahn

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 12:54
CPC Classifications
H; H01; H01F; H01F41/00; H01F41/14; Y; Y10; Y10S; Y10S205/00; Y10S205/922; Y10S428/00; Y10S428/922; Y10S428/923; Y10S428/924; Y10S428/926; Y10S428/9265; Y10S428/928; Y10S428/9335; Y10S428/934; Y10S428/935; Y10S428/936; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12535; Y10T428/12556; Y10T428/12569; Y10T428/12736; Y10T428/1275

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-08-06 1977-02-05 1977-08-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-08-06 1981-02-05 1981-08-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-08-06 1985-02-05 1985-08-07 $7700.00 Window Closed / Lapsed

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