US4510237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
In situ film hardening with aldehyde bisulfite and nonhardening aldehyde
Assignee: EIDP Inc
•
Filing: 1983-10-11
•
Granted: 1985-04-09
•
Expires: 2003-10-11
Abstract
Abstract A hardened photographic film is formed as a result of in situ generation of hardener by incorporating an aldehyde bisulfite in one layer and a nonhardening aldehyde in an adjacent layer. Preferred aldehyde bisulfite is glutaraldehyde bisulfite and preferred nonhardening aldehyde is orthosulfobenzaldehyde.
Inventors
- 👤 Reginald A. Booker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:09
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/30; G03C1/301
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
58 words
A process of forming a hardened photographic film in wich a layer comprised of silver halide dispersed in gelatin is coated on a support in contact with another layer and dried, characterized in that an aldehyde hardening agent is formed in situ by reacting an aldehyde bisulfite in one layer and a nonhardening aldehyde in an adjacent layer.
Claim 2
Dependent Claim
58 words
A process of forming a hardened photographic film in wich a layer comprised of silver halide dispersed in gelatin is coated on a support in contact with another layer and dried, characterized in that an aldehyde hardening agent is formed in situ by reacting an aldehyde bisulfite in one layer and a nonhardening aldehyde in an adjacent layer.
Claim 3
Dependent Claim
28 words
The process of claim 1 where the aldehyde bisulfite is -1,3-Dihydroxy-2,2-dihydroxymethyl-propane-1,3-disulphonic acid disodium salt, 1,4-Dihydroxymethyl-1,4(1',1"-disulphonic acid disodium salt) cyclohexane, 2,2,6,6-Tetrahydroxy-methyl-1,7-dihydroxy-heptane-1,7-disulphonic acid disodium salt or 1,5-Dihydroxypentane-1,7-disulphonic acid disodium salt.
Claim 4
Dependent Claim
15 words
The process of claim 1 where the nonhardening aldehyde is 4-Hydroxybenzaldehyde, 4-Nitrobenzaldehyde, Piperonal or Ortho-Sulfobenzaldehyde.
Claim 5
Dependent Claim
18 words
The process of claim 1 which comprises incorporating glutaraldehyde bisulfite in one layer and orthosulfobenzaldehyde in another layer.
Claim 6
Dependent Claim
19 words
The process of claim 1 wherein one of the reactant compounds is incorporated into the layer containing silver halide.
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) | 1988-04-08 | 1988-10-08 | 1989-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-08 | 1992-10-08 | 1993-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-08 | 1996-10-08 | 1997-04-09 | $7700.00 | Window Closed / Lapsed |