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US3702844A Expired / Lapsed US ⏱️ 0.0 years remaining

Polyvinyl alcohol-phosphoric acid films

Assignee: 3M Co
•
Filing: 1970-08-17
•
Granted: 1972-11-14
•
Expires: 1990-08-17
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Abstract

Abstract COATINGS AND SELF-SUPPORTING FILMS OF POLYVINYL ALCOHOL ARE PROVIDED, SAID FILMS AND COATINGS COMPRISING POLYVINYL ALCOHOL CONTAINING FROM 1 TO 20 PERCENT OF ORTHOPHOSPHORIC ACID, AND SAID FILM BEING COLORLESS, TRANSPARENT, SEMI-PERMEABLE, AND STRONG. THE FILMS AND COATINGS ARE DRIED AT OR NEAR ROOM TEMPERATURE AFTER BEING COATED.

Inventors

  • 👤 Ronald F Ofstead
  • 👤 Ramsis Gobran

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 08:06
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/30; C; C09; C09D; C09D129/00; C09D129/02; C09D129/04; G03C1/04; G03C1/053; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31855; Y10T428/3188; Y10T428/31895

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) 1975-11-14 1976-05-15 1976-11-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-11-14 1980-05-15 1980-11-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-11-14 1984-05-15 1984-11-14 $7700.00 Window Closed / Lapsed

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