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US3155531A Expired / Lapsed US ⏱️ 0.0 years remaining

Meagnetic liquid developer and method for electrostatic images

Assignee: Harris Graphics Corp
•
Filing: 1958-09-23
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Granted: 1964-11-03
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Expires: 1978-09-23
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Abstract

No abstract record available.

Inventors

  • 👤 Donald L Fauser
  • 👤 Edwin R Kolb

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 17:23
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/122; G03G13/00; G03G13/06; G03G13/10; G03G13/26; G03G13/28; G03G15/00; G03G15/06; G03G15/10; G03G15/108; G03G5/00; G03G5/005; G03G9/135; G03G9/1355

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 168 words
IN AN ELECTROPHOTOGRAPHIC PROCESS OF THE CHARACTER DESCRIBED IN WHICH AN ELECTROSTATIC CHARGE IMAGE IS PRODUCED ON AN ELECTROPHOTOGRAPHIC SURFACE, THE DEVELOPING STEPS WHICH COMPRISE IMMERSING SAID CHARGE IMAGE ON SAID SURFACE IN A NON-CONDUCTIVE LIQUID VEHICLE HAVING DISPERSED THEREIN A FINELY DIVIDED MAGNETIC DEVELOPER AGENT WHICH IS INSOLUBLE IN SAID VEHICLE AND CAPABLE OF ELECTROSTATIC ATTRACTION TO SAID SURFACE, DEPOSITING AND DEVELOPING AGENT ON SAID SURFACE IN ACCORDANCE WITH SAID CHARGE IMAGE THEREON, AND MAINTAINING IN SAID LIQUID VEHICLE ADJACENT SAID SURFACE A MAGNETIC FIELD OF A GRADIENT MAGNETICALLY ATTRACTING SAID DEVELOPER AGENT AWAY FROM SAID SURFACE AND OPPOSITELY TO SAID ELECTROSTATIC ATTRACTION OF SAID CHARGE IMAGE, THE STRENGTH OF SAID MAGNETIC ATTRACTION FOR SAID DEVELOPER AGENT AWAY FROM SAID SURFACE BEING LESS THAN THE STRENGTH OF SAID ELECTROSTATIC ATTRACTION OF SAID DEVELOPER AGENT TOWARD SAID CHARGE IMAGE ON SAID SURFACE FOR MINIMIZING DEPOSITION OF SAID DEVELOPER AGENT ON AREAS OF SAID SURFACE OTHER THAN AREAS OF SAID CHARGE IMAGE TO WHICH SAID AGENT IS ELECTRICALLY ATTRACTED.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1967-11-03 1968-05-04 1968-11-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1971-11-03 1972-05-04 1972-11-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1975-11-03 1976-05-04 1976-11-03 $7700.00 Window Closed / Lapsed

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