Patent DE616468C successfully refreshed from Google Patents.
US2582849A
Expired / Lapsed
US
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Phenylene diamine-formaldehyde resin preparation
Assignee: N V Octrooien Activit Mij
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Filing: 1947-12-26
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Granted: 1952-01-15
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Expires: 1967-12-26
Abstract
No abstract record available.
Inventors
- 👤 Ramondt Dirk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:23
CPC Classifications
B; B01; B01J; B01J41/00; B01J41/08; B01J41/12; B01J41/13
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
43 words
A PROCESS FOR THE MANUFACTURE OF AN ION EXCHANGE RESIN WHICH COMPRISES DROPPING IN THE FORM OF DROPS AN ACIDIC AQUEOUS MIXTURE OF METAPHENYLENE DIAMINE AND FORMALDEHYDE INTO A WARMER IMMISCIBLE LIQUID MAINTAINED AT A TEMPERATURE SUFFICIENT TO CAUSE POLYMERIZATION OF SAID MIXTURE.
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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) | 1955-01-14 | 1955-07-16 | 1956-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-01-14 | 1959-07-16 | 1960-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-01-14 | 1963-07-16 | 1964-01-15 | $7700.00 | Window Closed / Lapsed |