Patent US2985537A successfully refreshed from Google Patents.
US2985537A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rosin size having improved crystallization characteristics
Assignee: Hercules Powder Co
•
Filing: 1955-07-08
•
Granted: 1961-05-23
•
Expires: 1975-07-08
Abstract
No abstract record available.
Inventors
- 👤 Spencer H Watkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:20
CPC Classifications
C; C11; C11D; C11D15/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
65 words
A PASTE ROSIN SIZE HAVING IMPROVED STABILITY AGAINST CRYSTALLIZATION OBTAINED BY (1) REACTING ROSIN WITH FROM ABOUT 0.5 PERCENT TO ABOUT 4 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF ROSIN, OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE AND PARAFORMALDEHYDE IN THE PRESENCE OF AN ACID CATALYST AT TEMPERATURES ABOVE ABOUT 100*C. AND THEN PARTIALLY NEUTRALIZING THE RESULTING PRODUCT WITH AQUEOUS ALKALI.
Claim 2
Dependent Claim
65 words
A PASTE ROSIN SIZE HAVING IMPROVED STABILITY AGAINST CRYSTALLIZATION OBTAINED BY (1) REACTING ROSIN WITH FROM ABOUT 0.5 PERCENT TO ABOUT 4 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF ROSIN, OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF FORMALDEHYDE AND PARAFORMALDEHYDE IN THE PRESENCE OF AN ACID CATALYST AT TEMPERATURES ABOVE ABOUT 100*C. AND THEN PARTIALLY NEUTRALIZING THE RESULTING PRODUCT WITH AQUEOUS ALKALI.
References Cited (Backward Citations)
US2306281A
Cited
US1243312A
Cited
US2084213A
Cited
US2108928A
Cited
US2320795A
Cited
US2311781A
Cited
US2572071A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-05-22 | 1964-11-21 | 1965-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-05-22 | 1968-11-21 | 1969-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-05-22 | 1972-11-21 | 1973-05-23 | $7700.00 | Window Closed / Lapsed |