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US2865905A Expired / Lapsed US ⏱️ 0.0 years remaining

Plaster retarder and method of making same

Assignee: National Gypsum Co
•
Filing: 1954-07-13
•
Granted: 1958-12-23
•
Expires: 1974-07-13
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Abstract

No abstract record available.

Inventors

  • 👤 Robert R Teale

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 09:08
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/14; C04B24/00; C04B24/12; C04B24/14; Y; Y10; Y10S; Y10S530/00; Y10S530/859

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 74 words
THE METHOD OF MAKING HIGH STRENGTH RETARDER FOR GYPSUM PLASTER COMPRISING THE STEPS OF FORMING A SLURRY CONSISTING ESSENTIALLY OF 100 PARTS OF KERATIN, 20 TO 40 PARTS ALKALINE EARTH HYDROXIDE, AND 80 TO 250 PARTS WATER, MAINTAINING SAID SLURRY FREE OF ALKALI METAL COMPOUNDS, HYDROLYZING SAID SLURRY UNDER A PRESSURE GREATER THAN 30 LBS. PER SQ. IN. FOR A PERIOD OF 20 TO 90 MINUTES AT A TEMPERATURE OF FROM 220*F. TO 300*F.
Claim 2
Independent Claim 74 words
THE METHOD OF MAKING HIGH STRENGTH RETARDER FOR GYPSUM PLASTER COMPRISING THE STEPS OF FORMING A SLURRY CONSISTING ESSENTIALLY OF 100 PARTS OF KERATIN, 20 TO 40 PARTS ALKALINE EARTH HYDROXIDE, AND 80 TO 250 PARTS WATER, MAINTAINING SAID SLURRY FREE OF ALKALI METAL COMPOUNDS, HYDROLYZING SAID SLURRY UNDER A PRESSURE GREATER THAN 30 LBS. PER SQ. IN. FOR A PERIOD OF 20 TO 90 MINUTES AT A TEMPERATURE OF FROM 220*F. TO 300*F.

References Cited (Backward Citations)

US458743A Cited
US1308644A Cited
US2324951A Cited
US1106777A Cited
US1106778A Cited
US1787162A Cited
US1683539A Cited
US2212470A Cited
US2383252A Cited
US2368623A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1961-12-22 1962-06-23 1962-12-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-12-22 1966-06-23 1966-12-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-12-22 1970-06-23 1970-12-23 $7700.00 Window Closed / Lapsed

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