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Patent US2900407A successfully refreshed from Google Patents.
US2900407A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of spiro heterocyclic dithiophosphoric acids
Assignee: Union Carbide Corp
•
Filing: 1954-09-09
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Granted: 1959-08-18
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Expires: 1974-09-09
Abstract
No abstract record available.
Inventors
- 👤 William M Lanham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:15
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/547; C07F9/6564; C07F9/6571; C07F9/657109; C07F9/657127
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
13 words
AS NEW COMPOUNDS SPIRO HETEROCYCLIC DITHIOPHOSPHORIC ACIDS HAVING STRUCTURES CORRESPONDING TO THE FORMULA:
Claim 2
Dependent Claim
13 words
AS NEW COMPOUNDS SPIRO HETEROCYCLIC DITHIOPHOSPHORIC ACIDS HAVING STRUCTURES CORRESPONDING TO THE FORMULA:
Claim 3
Dependent Claim
10 words
PROCESS FOR PREPARING SPIRO HETEROCYCLIC DITHIOPHOSPHORIC ACIDS HAVING THE STRUCTURE:
Claim 4
Dependent Claim
10 words
PROCESS FOR PREPARING SPIRO HETEROCYCLIC DITHIOPHOSPHORIC ACIDS HAVING THE STRUCTURE:
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) | 1962-08-17 | 1963-02-16 | 1963-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-17 | 1967-02-16 | 1967-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-17 | 1971-02-16 | 1971-08-18 | $7700.00 | Window Closed / Lapsed |