Patent US2989521A successfully refreshed from Google Patents.
US2989521A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of cross-linking and oxidizing starch
Assignee: Individual
•
Filing: 1959-06-30
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Granted: 1961-06-20
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Expires: 1979-06-30
Abstract
No abstract record available.
Inventors
- 👤 Frederic R Senti
- 👤 Russell L Mellies
- 👤 Charles L Mehltretter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:45
CPC Classifications
C; C08; C08B; C08B31/00; C08B31/003; C08B31/006; C08B31/18; C08B31/185
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
102 words
THE METHOD OF TREATING STARCH TO MODIFY ITS HOTPASTE VISCOSITY WHILE PROVIDING STABILIZATION OF SAID MODIFIED VISCOSITY TO PROLONGED HEATING ALONG WITH IMPROVED CLARITY AND A MARKED RESISTANCE TO "SET-BACK," COMPRISING THE STEPS OF CROSS-LINKING UNTREATED STARCH IN ITS NATURAL GRANULAR STATE TO THE EXTENT OF ABOUT 25-300 AGU''S PER CROSS-LINK WITH EPICHLOROHYDRIN, OXIDIZING THE THUSLY CROSSLINKED STARCH WITH SODIUM HYPOCHLORITE IN THE PRESENCE OF SUBSTANTIAL FREE ALKALI AT A PH OF ABOUT 9 UNTIL THE STARCH CONTAINS BETWEEN ABOUT 9 AND ABOUT 3 MOLES OF CARBOXYL PER 100 ANHYDROGLUCOSE UNITS, AND RECOVERING THE CROSS-LINKED OXIDIZED STARCH PRODUCT IN UNGELATINIZED GRANULAR FORM.
Claim 2
Independent Claim
102 words
THE METHOD OF TREATING STARCH TO MODIFY ITS HOTPASTE VISCOSITY WHILE PROVIDING STABILIZATION OF SAID MODIFIED VISCOSITY TO PROLONGED HEATING ALONG WITH IMPROVED CLARITY AND A MARKED RESISTANCE TO "SET-BACK," COMPRISING THE STEPS OF CROSS-LINKING UNTREATED STARCH IN ITS NATURAL GRANULAR STATE TO THE EXTENT OF ABOUT 25-300 AGU''S PER CROSS-LINK WITH EPICHLOROHYDRIN, OXIDIZING THE THUSLY CROSSLINKED STARCH WITH SODIUM HYPOCHLORITE IN THE PRESENCE OF SUBSTANTIAL FREE ALKALI AT A PH OF ABOUT 9 UNTIL THE STARCH CONTAINS BETWEEN ABOUT 9 AND ABOUT 3 MOLES OF CARBOXYL PER 100 ANHYDROGLUCOSE UNITS, AND RECOVERING THE CROSS-LINKED OXIDIZED STARCH PRODUCT IN UNGELATINIZED GRANULAR FORM.
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) | 1964-06-19 | 1964-12-19 | 1965-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-19 | 1968-12-19 | 1969-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-19 | 1972-12-19 | 1973-06-20 | $7700.00 | Window Closed / Lapsed |