Patent US4483355A successfully refreshed from Google Patents.
US2540352A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making wet strength paper
Assignee: Munising Paper Co
•
Filing: 1945-10-27
•
Granted: 1951-02-06
•
Expires: 1965-10-27
Abstract
No abstract record available.
Inventors
- 👤 Schenck Willard Allan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:37
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/54; D21H17/55
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
101 words
IN A METHOD OF PREPARING ABSORPTIVE PAPER OF HIGH WET STRENGTH WITHOUT MATERIALLY CHANGING THE APPEARANCE AND FEEL THEREOF, THE IMPROVEMENT WHICH COMPRISES IMPREGNATING PAPER WITH A SOLUTION OF FORMALDEHYDE CONTAINING ABOUT 1 PER CENT OF A SYNTHETIC LINEAR POLYAMIDE WHICH CONSISTS OF THE POLYMERIZATION PRODUCT OF A LINEAR POLYMER-FORMING MATERIAL SELECTED FROM ONE OF THE GROUPS CONSISTING OF MONOAMINOCARBOXYLIC ACIDS AND MIXTURES OF DIAMINE WITH DIBASIC CARBOXYLIC ACID, AND DRYING SAID PAPER AFTER IMPREGNATION IN THE PRESENCE OF AN ACID CATALYST WHEREBY SAID PAPER IS SUBSTANTIALLY UNIFORMLY IMPREGNATED THROUGHOUT WITH FROM 0.5% TO 5.0% OF SAID SYNTHETIC LINEAR POLYAMIDE RESIN.
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) | 1954-02-05 | 1954-08-07 | 1955-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-05 | 1958-08-07 | 1959-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-05 | 1962-08-07 | 1963-02-06 | $7700.00 | Window Closed / Lapsed |