US3756909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Waterlaid leather substitute sheet and method for preparing the sheet
Assignee: 3M Co
•
Filing: 1972-09-26
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Granted: 1973-09-04
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Expires: 1992-09-26
Abstract
Abstract THE DISCLOSED SLURRIED SOLIDS COMPRISE BY WEIGHT: 2070% CATIONIC SOLIDS AND 80-30% ANIONIC POLYURETHANE LATEX SOLIDS, AT LEAST 30% OF THE CATIONIC SOLIDS BEING CHROME-TANNED LEATHER FIBERS AND AT LEAST 10%, PREFERABLY AT LEAST 25% OF THE CATIONIC SOLIDS BEING CATIONIZED WOOD FLOUR PARTICLES. THE SLURRY IS DEPOSITED ON A PAPERMAKING SCREEN IN THE CONVENTIONAL MANNER AND DRIED TO FORM SHOE INSOLE OR UPPER MATERIAL. HOT PRESSING CAN CONVERT THIS DRIED MATERIAL TO OUTSOLE MATERIAL.
Inventors
- 👤 A Stepan
- 👤 R Perkins
- 👤 A Griggs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:36
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/02; D21H13/00; D21H13/10; D21H13/28; D21H13/34; D21H17/20; D21H17/33; D21H17/46; D21H17/47; D21H17/49; D21H17/50; D21H17/51; D21H17/54; D21H17/57
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) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |