Patent US3938997A successfully refreshed from Google Patents.
US3938997A
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US
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Rapid access, air stable, regenerable iron chelate developer solutions
Assignee: 3M Co
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Filing: 1975-03-28
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Granted: 1976-02-17
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Expires: 1995-03-28
Abstract
Abstract Rapid access, air stable, regenerable iron chelate developers comprising at least three developer materials, at least one selected from each of the groups comprising: 1. iron chelate developers 2. an ascorbic acid and 3. phenidone, glycin, cysteine hydrochloride, hydroxylamine sulfate, hydroquinone monosulfonate and 4-amino-N-ethyl-N-(β-methanesulfoneamidoethyl)-m-toludine.
Inventors
- 👤 Richard S. Fisch
- 👤 Norman Newman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:37
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/30
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
65 words
A superadditive non-fixing developer solution comprising at least three developer materials, the solution comprising an iron chelating developer, a second developer selected from the group consisting of ascorbic acid, sugartype derivatives of ascorbic acid, and stereoisomers and diastereoisomers of ascorbic acid and its sugar-type derivatives, and a third developer selected from the group consisting of 1-phenyl-3-pyrazolidone, glycin, cysteine hydrochloride, hydroxylamine sulfate, 4-amino-N-ethyl-N-(β-methanesulfoneamidoethyl)-m-toluidine, and hydroquinone monosulfonate.
Claim 2
Dependent Claim
65 words
A superadditive non-fixing developer solution comprising at least three developer materials, the solution comprising an iron chelating developer, a second developer selected from the group consisting of ascorbic acid, sugartype derivatives of ascorbic acid, and stereoisomers and diastereoisomers of ascorbic acid and its sugar-type derivatives, and a third developer selected from the group consisting of 1-phenyl-3-pyrazolidone, glycin, cysteine hydrochloride, hydroxylamine sulfate, 4-amino-N-ethyl-N-(β-methanesulfoneamidoethyl)-m-toluidine, and hydroquinone monosulfonate.
Claim 3
Dependent Claim
23 words
The developer solution of claim 1 wherein the organic portion of the iron chelating developer is selected from ethylenediaminetetraacetic acid and diethylenetriaminepentaacetic acid.
Claim 4
Dependent Claim
17 words
The developer solution of claim 1 wherein the second developer is selected from ascorbic and isoascorbic acid.
Claim 5
Dependent Claim
41 words
The developer solution of claim 1 wherein the iron chelating developer is selected from ferrous ethylenediaminetetraacetic acid and ferrous diethylenetriaminepentaacetic acid, the second developer is selected from ascorbic and isoascorbic acid, and the third developer is selected from 1-phenyl-3-pyrazolidone and 4-amino-N-ethyl-N-(β-methanesulfoneamidoethyl)-m-toluidine.
Claim 6
Dependent Claim
46 words
The developer of claim 1 wherein the concentration of the iron chelate developer is at least 0.05M, the concentration of the second developer is at least 0.05M and the concentration of the third developer is less than that of the second developer and at least 0.1mM.
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) | 1979-02-16 | 1979-08-18 | 1980-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-16 | 1983-08-18 | 1984-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-16 | 1987-08-18 | 1988-02-17 | $7700.00 | Window Closed / Lapsed |