Patent US2446810A successfully refreshed from Google Patents.
US3790653A
Expired / Lapsed
US
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Polyester film base having uniform high optical density
Assignee: Eastman Kodak Co
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Filing: 1971-12-29
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Granted: 1974-02-05
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Expires: 1991-12-29
Abstract
Abstract BIAXIALLY-ORIENTED POLYESTER FILM BASE HAVING UNIFORM HIGH OPTICAL DENSITY AND FREE OF PINHOLES OR OTHER OPACITY DEFECTS IS PRODUCED BY FORMING A DISPERSION OF CARBON BLACK AND POLYVINYLPYRROLIDONE (PVP) IN ETHYLENE GLYCOL IN A HIGH SHEAR MILL, ADDING THE DISPERSION ALONG WITH POLYSTER FORMING REACTANTS TO AN ESTER EXCHANGE REACTOR, AND CARRYING OUT THE PRODUCTION OF THE POLYESTER MONOMER AND ITS SUBSEQUENT CONVERSION TO POLYESTER PREPOLYMER AND POLYESTER IN THE PRESENCE OF THE DISPERSED CARBON AND PVP.
Inventors
- 👤 K Barkey
- 👤 G Gandy
- 👤 D May
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:51
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/95; C; C08; C08K; C08K3/00; C08K3/02; C08K3/04; C08L; C08L67/00; C08L67/02; G03C1/825; C08L39/00; C08L39/04; C08L39/06
Claims Analysis
Total Claims: 0
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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) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |