US4153631A
Expired / Lapsed
US
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Process for processing silver halide developing agents
Assignee: Polaroid Corp
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Filing: 1977-04-05
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Granted: 1979-05-08
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Expires: 1997-04-05
Abstract
Abstract A process for preparing a silver halide developing agent of the formula: ##STR1## where R 1 can be the same or different substituent which will not impair the functionality of the compound as a silver halide developing agent. Specific substituents include hydrogen, alkyl radicals and alkoxy radicals among others. The silver halide developing agents are known as "ligand developers" and are particularly useful in diffusion transfer photographic products and processes.
Inventors
- 👤 Henry Bader
- 👤 Charles E. Whitten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:25
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/30; G03C5/3021; C; C07; C07C; C07C45/00; C07C45/56; C07C45/57; C07C45/60; C07C49/00; C07C49/587; C07C49/703; C07C49/747; C07D; C07D311/00; C07D311/02; C07D311/04; C07D311/58
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
119 words
A process which comprises the step of hydrating a cyclized compound of the Formula: ##STR8## in a medium comprising a mixture of water and a water miscible organic solvent where the water in said medium comprises from about 30% to about 60% by volume of the total volume of water and solvent, and an acid having a pKa between about 1.0 and about 3.0 in an amount sufficient to provide at least about 1 mole equivalent of acid per mole of cyclized compound to provide a compound of the Formula: ##STR9## where R 1 can be the same or different substituent chosen from those substituents which do not impair the functionality of said compound as a silver halide developer.
Claim 2
Dependent Claim
119 words
A process which comprises the step of hydrating a cyclized compound of the Formula: ##STR8## in a medium comprising a mixture of water and a water miscible organic solvent where the water in said medium comprises from about 30% to about 60% by volume of the total volume of water and solvent, and an acid having a pKa between about 1.0 and about 3.0 in an amount sufficient to provide at least about 1 mole equivalent of acid per mole of cyclized compound to provide a compound of the Formula: ##STR9## where R 1 can be the same or different substituent chosen from those substituents which do not impair the functionality of said compound as a silver halide developer.
Claim 3
Dependent Claim
22 words
A process of claim 1 where said acid is chosen from the group consisting of chloroacetic acid, dichloroacetic acid and mixtures thereof.
Claim 4
Dependent Claim
24 words
A process of claim 1 where said miscible organic solvent is chosen from the group consisting of methanol, ethanol, isopropanol, acetone and mixtures thereof.
Claim 5
Dependent Claim
24 words
A process of claim 1 where the water in said medium comprises about 50% by volume of the total volume of water and solvent.
Claim 6
Dependent Claim
90 words
A process which comprises the steps of hydrating a cyclized compound of the Formula: ##STR10## in a medium comprising a mixture of water and an organic miscible solvent where the water in said medium comprises from about 30% to about 60% by volume of the total volume of water and solvent, and an acid having a pKa between about 1.0 and about 3.0 in an amount sufficient to provide at least about 1 mole equivalent of acid per mole of cyclized compound to provide a compound of the Formula: ##STR11##
Claim 7
Dependent Claim
90 words
A process which comprises the steps of hydrating a cyclized compound of the Formula: ##STR10## in a medium comprising a mixture of water and an organic miscible solvent where the water in said medium comprises from about 30% to about 60% by volume of the total volume of water and solvent, and an acid having a pKa between about 1.0 and about 3.0 in an amount sufficient to provide at least about 1 mole equivalent of acid per mole of cyclized compound to provide a compound of the Formula: ##STR11##
Claim 8
Dependent Claim
22 words
A process of claim 5 where said acid is chosen from the group consisting of chloroacetic acid, dichloroacetic acid and mixtures thereof.
Claim 9
Dependent Claim
25 words
A process of claim 5 where said miscible organic solvent is chosen from the group consisting of methanol, ethanol, isopropanol, acetone and mixtures of these.
Claim 10
Dependent Claim
24 words
A process of claim 5 where the water in said medium comprises about 50% by volume of the total volume of water and solvent.
Claim 11
Dependent Claim
108 words
A process which comprises the step of hydrating a cyclized compound of the Formula: ##STR12## in a medium comprising a mixture of water and a water miscible organic solvent where the amount of water is between about 30% and about 60% by volume of total volume of the water and solvent chosen from the group consisting of methanol, ethanol, isopropanol, acetone and mixtures of these and an acid selected from the group consisting of chloroacetic acid, dichloroacetic acid or mixtures thereof in an amount sufficient to provide at least about 1 mole equivalent of acid per mole of cyclized compound to provide a compound of the Formula: ##STR13##
Claim 12
Dependent Claim
108 words
A process which comprises the step of hydrating a cyclized compound of the Formula: ##STR12## in a medium comprising a mixture of water and a water miscible organic solvent where the amount of water is between about 30% and about 60% by volume of total volume of the water and solvent chosen from the group consisting of methanol, ethanol, isopropanol, acetone and mixtures of these and an acid selected from the group consisting of chloroacetic acid, dichloroacetic acid or mixtures thereof in an amount sufficient to provide at least about 1 mole equivalent of acid per mole of cyclized compound to provide a compound of the Formula: ##STR13##
Claim 13
Dependent Claim
24 words
A process of claim 9 where the water in said medium comprises about 50% by volume of the total volume of water and solvent.
Claim 14
Dependent Claim
11 words
A process of claim 9 where said acid is chloroacetic acid.
Claim 15
Dependent Claim
11 words
A process of claim 9 where said acid is dichloroacetic acid.
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) | 1982-05-07 | 1982-11-06 | 1983-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-07 | 1986-11-06 | 1987-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-07 | 1990-11-06 | 1991-05-08 | $7700.00 | Window Closed / Lapsed |