US3900959A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined infra-red and air flow drying for photographic film
Assignee: 3M Co
•
Filing: 1973-05-07
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Granted: 1975-08-26
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Expires: 1993-05-07
Abstract
Abstract Photographic film is quickly and efficiently dried by a combination of infra-red radiation sources and independent nonheated air sources, which combination does not allow the film to be damaged by the drying process.
Inventors
- 👤 Enzo Breschi
- 👤 Mario Williner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:24
CPC Classifications
G; G03; G03D; G03D15/00; G03D15/02; G03D15/027; F; F26; F26B; F26B13/00; F26B13/10; F26B3/00; F26B3/28; F26B3/283; Y; Y10; Y10S; Y10S430/00; Y10S430/145
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
174 words
Apparatus for the drying of photographic film impregnated with water, said apparatus comprising a drying chamber provided with an inlet and outlet, at least one pair of nip rollers at least partially within said drying chamber for conveying film, said apparatus further characterized by a. at least two infra-red radiation sources on each side of the conveying plane of the film turnEd towards the conveying plane at a distance of from 1 to 3 cm., said at least two radiation sources having said at least one pair of nip rollers positioned between them, b. shields between all of said infra-red radiation sources and all of said nip rollers which prevent them from heating said nip rollers, c. means for supplying air at the surfaces of the film at a temperature of from 15* to 35*C, said sources directed towards the said conveying plane and placed on both sides of said plane, and d. paths within said chamber for conveying air away from said chamber after said air has been directed towards said conveying plane.
Claim 2
Dependent Claim
174 words
Apparatus for the drying of photographic film impregnated with water, said apparatus comprising a drying chamber provided with an inlet and outlet, at least one pair of nip rollers at least partially within said drying chamber for conveying film, said apparatus further characterized by a. at least two infra-red radiation sources on each side of the conveying plane of the film turnEd towards the conveying plane at a distance of from 1 to 3 cm., said at least two radiation sources having said at least one pair of nip rollers positioned between them, b. shields between all of said infra-red radiation sources and all of said nip rollers which prevent them from heating said nip rollers, c. means for supplying air at the surfaces of the film at a temperature of from 15* to 35*C, said sources directed towards the said conveying plane and placed on both sides of said plane, and d. paths within said chamber for conveying air away from said chamber after said air has been directed towards said conveying plane.
Claim 3
Dependent Claim
26 words
The apparatus of claim 1 in which each of said paths for conveying air away from said chamber are located adjacent to said sources of air.
Claim 4
Dependent Claim
28 words
The apparatus of claim 1 wherein the non-heated air flow is supplied at a rate sufficient that the film does not undergo a temperature increase higher than 10*C.
Claim 5
Dependent Claim
35 words
The apparatus of claim 1 in which each of said infra-red radiation sources has a said source of air and a said path for conveying air on each side of each said infra-red radiation source.
Claim 6
Dependent Claim
27 words
The apparatus of claim 1 in which there are two said sources of air and two said paths for conveying air about each said infra-red radiation source.
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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |