Patent US2769725A successfully refreshed from Google Patents.
US2769725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of cast calendering paper
Assignee: Warren SD Co
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Filing: 1953-03-20
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Granted: 1956-11-06
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Expires: 1973-03-20
Abstract
No abstract record available.
Inventors
- 👤 Robert T Hart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 12:01
CPC Classifications
D; D21; D21H; D21H19/00; D21H19/36; D21H19/44; D21H19/50; D21G; D21G9/00; D21G9/009; D21H25/00; D21H25/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
171 words
IN A PROCESS FOR PRODUCING A COATED PAPER HAVING A LEVEL SURFACE, COMPRISING APPLYING AQUEOUS LIQUID TO A DRY COATED SURFACE OF A COATED PAPER, THE COATING OF SUCH PAPER COMPRISING A HYDROPHILIC SWELLABLE PROTEIN, TO WET SAID DRY COATING SURFACE AND IMMEDIIATELY THEREAFTER PRESSING SAID WETTED COATING SURFACE AGAINST A HIGHLY POLISHED, SMOOTH, FINISHING SURFACE WITH WHICH SAID WETTED COATING SURFACE IS KEPT IN CONTACT WHILE MOISTURE IS EVAPORATED THEREFROM AND THEREAFTER REMOVED, THE IMPROVEMENT COMPRISING CONTACTING SAID WETTED COATING SURFACE, BEFORE IT IS PRESSED AGAINST SAID FINISHING SURFACE, WITH FORMALDEHYDE, AND MAINTAINING THE SURFACE OF THE COATING IN CONTACT WITH THE FINISHING SURFACE WHILE THE PH OF THE SURFACE OF THE COATING IS MAINTAINED BETWEEN 7.3 AND 9 BY THE PRESENCE OF A MEMBER OF THE GROUP CONSISTING OF AMINES AND QUATERNARY AMMONIUM HYDROXIDES HAVING A BOILING POINT ABOVE ABOUT 125* C. AND A BASIC IONIZATION CONSTANT BETWEEN ABOUT 10-3 AND 10-7 AND UNTIL THE TIME WHEN THE COATED SURFACE IS REMOVED FROM THE CONTACT WITH THE FINISHING SURFACE.
Claim 2
Dependent Claim
171 words
IN A PROCESS FOR PRODUCING A COATED PAPER HAVING A LEVEL SURFACE, COMPRISING APPLYING AQUEOUS LIQUID TO A DRY COATED SURFACE OF A COATED PAPER, THE COATING OF SUCH PAPER COMPRISING A HYDROPHILIC SWELLABLE PROTEIN, TO WET SAID DRY COATING SURFACE AND IMMEDIIATELY THEREAFTER PRESSING SAID WETTED COATING SURFACE AGAINST A HIGHLY POLISHED, SMOOTH, FINISHING SURFACE WITH WHICH SAID WETTED COATING SURFACE IS KEPT IN CONTACT WHILE MOISTURE IS EVAPORATED THEREFROM AND THEREAFTER REMOVED, THE IMPROVEMENT COMPRISING CONTACTING SAID WETTED COATING SURFACE, BEFORE IT IS PRESSED AGAINST SAID FINISHING SURFACE, WITH FORMALDEHYDE, AND MAINTAINING THE SURFACE OF THE COATING IN CONTACT WITH THE FINISHING SURFACE WHILE THE PH OF THE SURFACE OF THE COATING IS MAINTAINED BETWEEN 7.3 AND 9 BY THE PRESENCE OF A MEMBER OF THE GROUP CONSISTING OF AMINES AND QUATERNARY AMMONIUM HYDROXIDES HAVING A BOILING POINT ABOVE ABOUT 125* C. AND A BASIC IONIZATION CONSTANT BETWEEN ABOUT 10-3 AND 10-7 AND UNTIL THE TIME WHEN THE COATED SURFACE IS REMOVED FROM THE CONTACT WITH THE FINISHING SURFACE.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-11-06 | 1960-05-07 | 1960-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-11-06 | 1964-05-07 | 1964-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-11-06 | 1968-05-07 | 1968-11-06 | $7700.00 | Window Closed / Lapsed |