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US3640984A Expired / Lapsed US ⏱️ 0.0 years remaining

Polytetrafluoroethylene

Assignee: Solvay Solexis Inc
•
Filing: 1963-11-04
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Granted: 1972-02-08
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Expires: 1983-11-04
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Abstract

Abstract 1. A METHOD FOR PREPARING POLYTETRAFLUOROETHYLENE ADAPTED FOR MOLDING PRECISION PARTS AND THIN SHEETING, COMPRISING THE SEQUENTIAL STEPS OF (A) SUBJECTING PARTICLES OF POLYTETRAFLUOROETHYLENE, WHICH PARTICLES ARE AT LEAST 100 MICRONS IN THEIR SMALLEST DIMENSION, TO MILLING EFFECTED SUBSTANTIALLY SOLELY BY INTERPARTICULATE COLLISION, AT A TEMPERATURE OF LESS THAN ABOUT 200*F.; (B) CLASSIFYING THE MILLED PARTICLES TO SEPARATE THEREFROM PARTICLES HAVING A MAXIMUM DIMENSION OF UP TO AND INCLUDING ABOUT 50 MICRONS, WET-SIEVE SIZE; AND (C) SUBJECTING THE UNSEPARATED PARTICLES OF LARGER THAN ABOUT 50 MICRONS, WET-SIEVE SIZE, REPEATEDLY TO THE MILLING EFFECTED SUBSTANTIALLY SOLELY BY INTERPARTICULATE COLLISION, AT A TEMPERATURE OF LESS THAN ABOUT 200*F.

Inventors

  • 👤 William A Miller

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 16:24
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; B; B02; B02C; B02C19/00; B02C19/0012; B02C19/005; B02C19/06; B02C19/063; B02C23/00; B29; B29B; B29B13/00; B29B13/10; B29C; B29C43/00; B29C43/006; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 105 words
A METHOD FOR PREPARING POLYTETRAFLUOROETHYLENE ADAPTED FOR MOLDING PRECISION PARTS AND THIN SHEETING, COMPRISING THE SEQUENTIAL STEPS OF (A) SUBJECTING PARTICLES OF POLYTETRAFLUOROETHYLENE, WHICH PARTICLES ARE AT LEAST 100 MICRONS IN THEIR SMALLEST DIMENSION, TO MILLING EFFECTED SUBSTANTIALLY SOLELY BY INTERPARTICULATE COLLISION, AT A TEMPERATURE OF LESS THAN ABOUT 200*F.; (B) CLASSIFYING THE MILLED PARTICLES TO SEPARATE THEREFROM PARTICLES HAVING A MAXIMUM DIMENSION OF UP TO AND INCLUDING ABOUT 50 MICRONS, WET-SIEVE SIZE; AND (C) SUBJECTING THE UNSEPARATED PARTICLES OF LARGER THAN ABOUT 50 MICRONS, WET-SIEVE SIZE, REPEATEDLY TO THE MILLING EFFECTED SUBSTANTIALLY SOLELY BY INTERPARTICULATE COLLISION, AT A TEMPERATURE OF LESS THAN ABOUT 200*F.
Claim 2
Independent Claim 105 words
A METHOD FOR PREPARING POLYTETRAFLUOROETHYLENE ADAPTED FOR MOLDING PRECISION PARTS AND THIN SHEETING, COMPRISING THE SEQUENTIAL STEPS OF (A) SUBJECTING PARTICLES OF POLYTETRAFLUOROETHYLENE, WHICH PARTICLES ARE AT LEAST 100 MICRONS IN THEIR SMALLEST DIMENSION, TO MILLING EFFECTED SUBSTANTIALLY SOLELY BY INTERPARTICULATE COLLISION, AT A TEMPERATURE OF LESS THAN ABOUT 200*F.; (B) CLASSIFYING THE MILLED PARTICLES TO SEPARATE THEREFROM PARTICLES HAVING A MAXIMUM DIMENSION OF UP TO AND INCLUDING ABOUT 50 MICRONS, WET-SIEVE SIZE; AND (C) SUBJECTING THE UNSEPARATED PARTICLES OF LARGER THAN ABOUT 50 MICRONS, WET-SIEVE SIZE, REPEATEDLY TO THE MILLING EFFECTED SUBSTANTIALLY SOLELY BY INTERPARTICULATE COLLISION, AT A TEMPERATURE OF LESS THAN ABOUT 200*F.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-02-07 1975-08-09 1976-02-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-02-07 1979-08-09 1980-02-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-02-07 1983-08-09 1984-02-08 $7700.00 Window Closed / Lapsed

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