US3647449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Neutralizing bath for use in photographic processing
Assignee: Eastman Kodak Co
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Filing: 1970-06-08
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Granted: 1972-03-07
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Expires: 1990-06-08
Abstract
Abstract A neutralizing bath, employed in processing photographic elements to neutralize residual aldehyde resulting from prior treatment in an aldehydic prehardening bath and thereby to avoid the deleterious effects of carry through of the aldehyde into subsequent processing baths, is comprised of hydroxylamine or a water-soluble acid addition salt thereof and an hydroxyalkylidene diphosphonic acid or water-soluble salt thereof. The hydroxylamine serves to neutralize the aldehyde by reacting therewith, while the hydroxyalkylidene diphosphonic acid serves to stabilize the bath and facilitate its long term storage by inhibiting decomposition of the hydroxylamine.
Inventors
- 👤 Richard J Malloy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:51
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/268
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
53 words
A neutralizing bath as described in claim 1 wherein said aldehyde-neutralizing agent is present in an amount of about 1 to about 100 grams per liter of solution and said hydroxyalkylidene diphosphonic acid or water-soluble salt thereof is present in an amount of about 0.5 to about 25 grams per liter of solution.
Claim 2
Dependent Claim
23 words
A neutralizing bath as described in claim 2 wherein said aldehyde-neutralizing agent is hydroxylamine sulfate and said hydroxyalkylidene diphosphonic acid is 1-hydroxyethylidene-1,1-diphosphonic acid.
References Cited (Backward Citations)
US3214454A
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US3141771A
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US3201246A
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US3168400A
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US3488707A
Cited
US3431217A
Cited
US3502577A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-03-07 | 1975-09-06 | 1976-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-07 | 1979-09-06 | 1980-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-07 | 1983-09-06 | 1984-03-07 | $7700.00 | Window Closed / Lapsed |