Patent US3222244A successfully refreshed from Google Patents.
US3222244A
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Process for producing water-laid sheets from polyamide fibers pretreated with a tannin
Assignee: Glanzstoff AG
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Filing: 1963-02-04
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Granted: 1965-12-07
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Expires: 1983-02-04
Abstract
No abstract record available.
Inventors
- 👤 Sommer Erwin
- 👤 Gerlach Klaus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:25
CPC Classifications
D; D21; D21H; D21H13/00; D21H13/10; D21H13/20; D21H13/26
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
94 words
IN A PROCESS FOR THE PRODUCTION OF A FIBROUS SHEET MATERIAL BY WATER-LAYING SYNTHETIC POLYAMIDE FIBERS ONTO A SUPPORTING SURFACE AND WITHDRAWING WATER FROM THE RESULTING FIBROUS WEB, THE IMPROVEMENT WHICH COMPRISES: PRETREATING SAID FIBERS IN AN AQUEOUS BATH CONTAINING AN ORGANIC TANNIN HAVING A MOLECULAR WEIGHT OF ABOUT 200 TO 1000, SAID AQUEOUS BATH BEING MAINTAINED AT A PH OF ABOUT 1 TO 4.5; REMOVING EXCESS BATH LIQUOR FROM SAID FIBERS; AND THEN DISPERSING THE PRETREATED FIBERS INTO WATER TO FORM AN AQUEOUS PULP SLURRY SUITABLE FOR SAID WATERLAYING OF A FIBROUS WEB.
Claim 2
Dependent Claim
94 words
IN A PROCESS FOR THE PRODUCTION OF A FIBROUS SHEET MATERIAL BY WATER-LAYING SYNTHETIC POLYAMIDE FIBERS ONTO A SUPPORTING SURFACE AND WITHDRAWING WATER FROM THE RESULTING FIBROUS WEB, THE IMPROVEMENT WHICH COMPRISES: PRETREATING SAID FIBERS IN AN AQUEOUS BATH CONTAINING AN ORGANIC TANNIN HAVING A MOLECULAR WEIGHT OF ABOUT 200 TO 1000, SAID AQUEOUS BATH BEING MAINTAINED AT A PH OF ABOUT 1 TO 4.5; REMOVING EXCESS BATH LIQUOR FROM SAID FIBERS; AND THEN DISPERSING THE PRETREATED FIBERS INTO WATER TO FORM AN AQUEOUS PULP SLURRY SUITABLE FOR SAID WATERLAYING OF A FIBROUS WEB.
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) | 1968-12-06 | 1969-06-07 | 1969-12-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-12-06 | 1973-06-07 | 1973-12-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-12-06 | 1977-06-07 | 1977-12-07 | $7700.00 | Window Closed / Lapsed |