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Patent US2035362A successfully refreshed from Google Patents.
US2035362A
Expired / Lapsed
US
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Manufacture of stable sulphuric acid esters of leuco derivatives of vat dyestuffs
Assignee: Durand and Huguenin AG
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Filing: 1931-07-25
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Granted: 1936-03-24
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Expires: 1951-07-25
Abstract
No abstract record available.
Inventors
- 👤 Bauer Wilhelm
- 👤 Zeh Ludwig
- 👤 Bollweg Bernhard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:04
CPC Classifications
C; C09; C09B; C09B9/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1939-03-24 | 1939-09-23 | 1940-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1943-03-24 | 1943-09-23 | 1944-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1947-03-24 | 1947-09-23 | 1948-03-24 | $7700.00 | Window Closed / Lapsed |