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US4166728A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for conducting ammonia in copying machines

Assignee: Hoechst AG
•
Filing: 1977-07-28
•
Granted: 1979-09-04
•
Expires: 1997-07-28
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Abstract

Abstract This invention relates to a process for conducting ammonia in a diazo copying machine which comprises passing ammonia-containing exhaust air by first conduit means from a developing station of said copying machine through a cooled heat exchanger in which the ammonia and water is frozen out, then heating said heat exchanger to a temperature at which the water and the ammonia are liquified, passing the mixture of liquified water and liquified ammonia to a releasing station, adding fresh ammonia water to the liquified water and to the liquified ammonia, passing it together with the liquified water and liquified ammonia in the releasing station counter-currently to vapor produced by a vapor-generating means, and conducting the gaseous ammonia to the developing station, said process employing two heat exchangers, the first heat exchanger through which the exhaust air is passed being cooled and the second heat exchanger being heated for liquifying the ammonia and water frozen out during the preceding process step, whereby the second heat exchanger is cooled and the first heat exchanger is heated.

Inventors

  • 👤 Karl-Heinz Degenhardt
  • 👤 Hermann Frank
  • 👤 Gerhard Marx

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 16:22
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/02; B01D53/04; B01D53/0407; B01D53/0438; B01D53/0423; B01D53/06; G; G03; G03D; G03D7/00; B01D2253/00; B01D2253/10; B01D2253/106; B01D2253/108; B01D2253/30; B01D2253/302; B01D2253/308; B01D2257/00; B01D2257/40; B01D2257/406; B01D2257/80; B01D2259/00; B01D2259/40; B01D2259/40003; B01D2259/40083; B01D2259/40088; B01D2259/406; B01D2259/4061

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 169 words
A process for conducting ammonia in a diazo copying machine which comprises passing ammonia-containing exhaust air by first conduit means from a developing station of said copying machine through a cooled heat exchanger in which the ammonia and water is frozen out, then heating said heat exchanger to a temperature at which the water and the ammonia are liquified, passing the mixture of liquified water and liquified ammonia to a releasing station, adding fresh ammonia water to the liquified water and to the liquified ammonia, passing it together with the liquified water and liquified ammonia in the releasing station counter-currently to vapor produced by a vapor-generating means, and conducting the gaseous ammonia to the developing station, said process employing two heat exchangers, the first heat exchanger through which the exhaust air is passed being cooled and the second heat exchanger being heated for liquifying the ammonia and water frozen out during the preceding process step, whereby the second heat exchanger is cooled and the first heat exchanger is heated.
Claim 2
Dependent Claim 169 words
A process for conducting ammonia in a diazo copying machine which comprises passing ammonia-containing exhaust air by first conduit means from a developing station of said copying machine through a cooled heat exchanger in which the ammonia and water is frozen out, then heating said heat exchanger to a temperature at which the water and the ammonia are liquified, passing the mixture of liquified water and liquified ammonia to a releasing station, adding fresh ammonia water to the liquified water and to the liquified ammonia, passing it together with the liquified water and liquified ammonia in the releasing station counter-currently to vapor produced by a vapor-generating means, and conducting the gaseous ammonia to the developing station, said process employing two heat exchangers, the first heat exchanger through which the exhaust air is passed being cooled and the second heat exchanger being heated for liquifying the ammonia and water frozen out during the preceding process step, whereby the second heat exchanger is cooled and the first heat exchanger is heated.

References Cited (Backward Citations)

US2116191A Cited
US2500291A Cited
US3570383A Cited
US3720150A Cited
GB1365759A Cited
DE2337961A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-09-03 1983-03-05 1983-09-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-09-03 1987-03-05 1987-09-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-09-03 1991-03-05 1991-09-04 $7700.00 Window Closed / Lapsed

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