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US4175969A Expired / Lapsed US ⏱️ 0.0 years remaining

Antistatic photographic X-ray film having a uniform protective surface coating of surfactant oligomer of tetrafluoroethylene

Assignee: Eastman Kodak Co
•
Filing: 1978-03-17
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Granted: 1979-11-27
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Expires: 1998-03-17
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Abstract

Abstract This invention relates to photographic elements having a coatable, non-photoactive protective surface of improved antistatic properties. The improvement is accomplished by incorporation into this layer of an anionic fluorocarbon surfactant which is characterized by being low molecular weight oligomers of tetrafluoroethylene. In a preferred embodiment of the invention, a gelatin surface protective layer of an X-ray film includes about 1.0-3.5% by weight, based on the gelatin solids of the layer, of oligomers of tetrafluoroethylene having a large amount of hydrophilic fluoroalkyl branching in the fluorocarbon chain.

Inventors

  • 👤 E. Scudder Mackey

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 07:53
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/38; G03C1/385; G03C1/76; G03C1/7614; G03C5/00; G03C5/16; Y; Y10; Y10S; Y10S260/00; Y10S260/15

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 90 words
An X-ray sensitive photographic element having an antistatic and protective layer thereon which is a uniform, coatable, non-photoactive gelatin-containing composition exhibiting an excellent sensitometric response comprising about 1 to about 3.5% by weight, based upon the gelatin content of said composition, of a fluorocarbon surfactant which is a mixture of low molecular weight oligomers of tetrafluoroethylene having hydrophilic fluorocarbon branching in the fluorocarbon chain, wherein said oligomers have the formula (C 2 F 4 ) n , where n is 4, 5 or 6, and comprise primarily the pentamer oligomer.
Claim 2
Dependent Claim 90 words
An X-ray sensitive photographic element having an antistatic and protective layer thereon which is a uniform, coatable, non-photoactive gelatin-containing composition exhibiting an excellent sensitometric response comprising about 1 to about 3.5% by weight, based upon the gelatin content of said composition, of a fluorocarbon surfactant which is a mixture of low molecular weight oligomers of tetrafluoroethylene having hydrophilic fluorocarbon branching in the fluorocarbon chain, wherein said oligomers have the formula (C 2 F 4 ) n , where n is 4, 5 or 6, and comprise primarily the pentamer oligomer.
Claim 3
Dependent Claim 18 words
A composition according to claim 1 wherein said oligomers constitute about 1.5% by weight of the gelatin solids.

References Cited (Backward Citations)

US3589906A Cited
US3850642A Cited
US3779768A Cited
US3753716A Cited
US3775126A Cited
US3884699A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-11-26 1983-05-28 1983-11-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-11-26 1987-05-28 1987-11-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-11-26 1991-05-28 1991-11-27 $7700.00 Window Closed / Lapsed

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