US3915712A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and an apparatus for improving the properties of solutions having a high solids content, which are to be used for coating a tape particularly solutions of photographic emulsions
Assignee: Agfa Gevaert AG
•
Filing: 1973-09-28
•
Granted: 1975-10-28
•
Expires: 1993-09-28
Abstract
Abstract A process and apparatus for improving and maintaining the concentration, and homogeneity of gelatino silver halide emulsions with a high solids content reservoir bath for tape coating a photographic emulsion, wherein the coating emulsion is partly withdrawn from the bath and circulated through a known type of falling film evaporator to which a vacuum is applied and processed to concentrate, degasify and homogenize the withdrawn emulsion. A ballast steam under high velocity is injected into the falling film of emulsion to act on the emulsion.
Inventors
- 👤 Peter Herzhoff
- 👤 Fritz Maus
- 👤 Hans Gref
- 👤 Stephan Platz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:26
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/025; B; B01; B01D; B01D1/00; B01D1/06; B01D1/065; B01D3/00; B01D3/10; G03C2200/00; G03C2200/09; G03C2200/60; Y; Y10; Y10S; Y10S159/00; Y10S159/16; Y10S159/21; Y10S430/00; Y10S430/136
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
185 words
IN THE PROCESS OF COATING STRIP-FROM SUBSTRATES WITH A COATING OF GELATINO-SILVER HALIDE EMULSION OF UNIFORM HOMOGENEITY AND CONTROLLED VISCOSITY, THE SUBSTRATE BEING WETTED IN A RESEVIOR IN WHICH THE EMULSION IS SUPPLIED TO THE SUBSTRATE THE IMPROVEMENT WHICH CONSISTS OF CONTINUOUSLY WITHDRAWING A PORTION OF GELATINO-SILVER HALIDE EMULSION HAVING A CERTAN SOLIDS CONTENT FROM THE RESERVIOR, MIXING SAID WITHDRAWN EMULSION IN A MIXING STEP WITH AN ADDITIONAL SUPPLY OF GELATINO-SILVER HALIDE EMULSION HAVING A VISCOSITY OF 20*400CP, REGULATING THE RATE OF ADDITIONAL SUPPLY AT A VALUE THAT THE LIQUID LEEL IN TE COATING RESEVIOR IS KEPT CONSTANT, INTRODUCING THE MIXED EMULSION FROM SAID MIXING STEP INTO THE HEAD OF AN EVAPORATED COLUMN AT A PRESSURE RANGING FROM 150 TO 250 MM HG AND A TEMPERATURE OF BETWEEN 60* AND 72*C, MOVING A THIN FILM OF SAID EMULSION IN A FALLING FILM DOWNWARDLY OVER A HEATED SURFACE IN A VERTICAL COLUMN FROM THE HEAD, INJECTING A QUANTUITY OF BALLAST STREAM AT A HIGH VELOCITY AGAINST SAID THIN ILM THE EMULSION FLOWING DOWN THE HEATED SURFACE OF EVAPORATION CHAMBER, SHEARING THE DOWNWARDLY FLOWING EMULSION WITH THE
Claim 2
Dependent Claim
185 words
IN THE PROCESS OF COATING STRIP-FROM SUBSTRATES WITH A COATING OF GELATINO-SILVER HALIDE EMULSION OF UNIFORM HOMOGENEITY AND CONTROLLED VISCOSITY, THE SUBSTRATE BEING WETTED IN A RESEVIOR IN WHICH THE EMULSION IS SUPPLIED TO THE SUBSTRATE THE IMPROVEMENT WHICH CONSISTS OF CONTINUOUSLY WITHDRAWING A PORTION OF GELATINO-SILVER HALIDE EMULSION HAVING A CERTAN SOLIDS CONTENT FROM THE RESERVIOR, MIXING SAID WITHDRAWN EMULSION IN A MIXING STEP WITH AN ADDITIONAL SUPPLY OF GELATINO-SILVER HALIDE EMULSION HAVING A VISCOSITY OF 20*400CP, REGULATING THE RATE OF ADDITIONAL SUPPLY AT A VALUE THAT THE LIQUID LEEL IN TE COATING RESEVIOR IS KEPT CONSTANT, INTRODUCING THE MIXED EMULSION FROM SAID MIXING STEP INTO THE HEAD OF AN EVAPORATED COLUMN AT A PRESSURE RANGING FROM 150 TO 250 MM HG AND A TEMPERATURE OF BETWEEN 60* AND 72*C, MOVING A THIN FILM OF SAID EMULSION IN A FALLING FILM DOWNWARDLY OVER A HEATED SURFACE IN A VERTICAL COLUMN FROM THE HEAD, INJECTING A QUANTUITY OF BALLAST STREAM AT A HIGH VELOCITY AGAINST SAID THIN ILM THE EMULSION FLOWING DOWN THE HEATED SURFACE OF EVAPORATION CHAMBER, SHEARING THE DOWNWARDLY FLOWING EMULSION WITH THE
References Cited (Backward Citations)
US2779724A
Cited
US3502494A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |