US3282870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Starch and polycarboxamide reaction products
Assignee: Dow Chemical Co
•
Filing: 1963-11-29
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Granted: 1966-11-01
•
Expires: 1983-11-29
Abstract
No abstract record available.
Inventors
- 👤 David E Harmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:12
CPC Classifications
C; C08; C08B; C08B31/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
91 words
A METHOD WHICH COMPRISES THE STEPS OF: MUTUALLY DISSOLVING A WATER-SOLVING POLYALKANE HAVING A PLURALITY OF SUBSTITUENT CARBOXAMIDE GROUPS AND A WATER-SOLUBLE STARCH PRODUCT IN AN INERT AQUEOUS SOLVENT; HEATING THE RESULTING SOLUTION AT AN ELEVATED TEMPERATURE WITHIN THE RANGE FROM ABOUT 50 TO ABOUT 200* C. UNDER A PRESSURE SUFFICIENT TO MAINTAIN THE DESIRED REACTION TEMPERATURE WHEREBY A WATER-SWELLABLE REACTION PRODUCT IS OBTAINED; SEPARATING THE REATION PRODUCT FROM THE INERT REACTION MEDIUM AND INCLUDING THE ADDITIONAL SEQUENTIAL STEP OF DRYING AND PULVERIZING THE INTERACTION PRODUCT OBTAINED FROM THE REACTION MEDIUM.
Claim 2
Independent Claim
91 words
A METHOD WHICH COMPRISES THE STEPS OF: MUTUALLY DISSOLVING A WATER-SOLVING POLYALKANE HAVING A PLURALITY OF SUBSTITUENT CARBOXAMIDE GROUPS AND A WATER-SOLUBLE STARCH PRODUCT IN AN INERT AQUEOUS SOLVENT; HEATING THE RESULTING SOLUTION AT AN ELEVATED TEMPERATURE WITHIN THE RANGE FROM ABOUT 50 TO ABOUT 200* C. UNDER A PRESSURE SUFFICIENT TO MAINTAIN THE DESIRED REACTION TEMPERATURE WHEREBY A WATER-SWELLABLE REACTION PRODUCT IS OBTAINED; SEPARATING THE REATION PRODUCT FROM THE INERT REACTION MEDIUM AND INCLUDING THE ADDITIONAL SEQUENTIAL STEP OF DRYING AND PULVERIZING THE INTERACTION PRODUCT OBTAINED FROM THE REACTION MEDIUM.
References Cited (Backward Citations)
US2804436A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-10-31 | 1970-05-02 | 1970-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-10-31 | 1974-05-02 | 1974-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-10-31 | 1978-05-02 | 1978-11-01 | $7700.00 | Window Closed / Lapsed |