Patent US3781120A successfully refreshed from Google Patents.
US2536893A
Expired / Lapsed
US
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Production of alkali-resistant alginate materials
Assignee: Alginate Industries Ltd
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Filing: 1948-04-22
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Granted: 1951-01-02
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Expires: 1968-04-22
Abstract
No abstract record available.
Inventors
- 👤 Speakman John Bamber
- 👤 Chamberlain Norman Henry
- 👤 Dorkin Catherine Marga Cameron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 00:07
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/04; C; C08; C08B; C08B37/00; C08B37/006; C08B37/0084
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
78 words
A PROCESS OF PREPARATION OF ALKALI-RESISTANT ALGINATE MATERIAL CONSISTING IN ESTERIFYING AND ETHERIFYING AN ALGINIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF ALGINIC ACID AND WATERINSOLUBLE METAL ALINATES HAVING AT LEAST A PART OF THEIR CARBOXYL GROUPS FREE, WITH AN ALIPHATIC HYDROCARBON EPOXY COMPOUND HAVING TWO EPOXY GROUPS CONTAINING OXYGEN LINKING TWO ADJOINING CARBONS ONLY, UNTIL THE EPOXY COMPOUND HAS COMBINED WITH BOTH HYDROXY AND CARBOXYL GROUPS OF MOLECULES OF THE ALIGNATE MATERIAL AND SO LINKED THEM TOGETHER.
Claim 2
Dependent Claim
78 words
A PROCESS OF PREPARATION OF ALKALI-RESISTANT ALGINATE MATERIAL CONSISTING IN ESTERIFYING AND ETHERIFYING AN ALGINIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF ALGINIC ACID AND WATERINSOLUBLE METAL ALINATES HAVING AT LEAST A PART OF THEIR CARBOXYL GROUPS FREE, WITH AN ALIPHATIC HYDROCARBON EPOXY COMPOUND HAVING TWO EPOXY GROUPS CONTAINING OXYGEN LINKING TWO ADJOINING CARBONS ONLY, UNTIL THE EPOXY COMPOUND HAS COMBINED WITH BOTH HYDROXY AND CARBOXYL GROUPS OF MOLECULES OF THE ALIGNATE MATERIAL AND SO LINKED THEM TOGETHER.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-01-01 | 1954-07-03 | 1955-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-01-01 | 1958-07-03 | 1959-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-01-01 | 1962-07-03 | 1963-01-02 | $7700.00 | Window Closed / Lapsed |