US3681492A
Expired / Lapsed
US
⏱️ 0.0 years remaining
A bactericidal stabilized ascorbic acid composition
Assignee: Allergan Inc
•
Filing: 1969-10-30
•
Granted: 1972-08-01
•
Expires: 1989-10-30
Abstract
Abstract Microbially active aqueous solutions of an ascorbic acid material have been prepared which have a prolonged microbicidal life. The aforesaid aqueous solution initially contains very small amounts of cupric ion (or sometimes cuprous ion), on the order of 25 to 50 micrograms per milliliter of aqueous solution, in the presence of at least a sufficient amount of a watersoluble amine or water-soluble ammonium salt, to complex the copper ions present, the first log stability constant (k1) of the copper-amine complex and the copper-ammonium complex so formed in the aqueous solution lying in the range of between about 3 to 14 at a pH of beteween about 5 to 8.
Inventors
- 👤 Judith M Kotzbauer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:58
CPC Classifications
A; A01; A01N; A01N43/00; A01N43/02; A01N43/04; A01N43/06; A01N43/08
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |