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US3259991A Expired / Lapsed US ⏱️ 0.0 years remaining

Freeze drying method and apparatus

Assignee: Abbott Laboratories
•
Filing: 1965-01-07
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Granted: 1966-07-12
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Expires: 1985-01-07
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Abstract

No abstract record available.

Inventors

  • 👤 Jr George M Illich

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 11:38
CPC Classifications
F; F26; F26B; F26B5/00; F26B5/04; F26B5/06

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 150 words
A METHOD OF DRYING A TEMPERATURE SENSITIVE MATERIAL IN A VACUUM CHAMBER HAVING IN COMMUNICATION THEREWITH A THERMOCOUPLE TYPE VACUUM GAUGE AND AN IONIZATION TYPE VACUUM GAUGE, COMPRISING THE STEPS OF: FREEZING THE MATERIAL; PLACING THE FROZEN MATERIAL IN THE VACUUM CHAMBER; APPLYING HEAT AND VACUUM TO THE VACUUM CHAMBER TO REMOVE MOISTURE FROM THE MATERIAL BEING DRIED; CALIBRATING THE THERMOCOUPLE TYPE VACUUM GAUGE AND THE IONIZATION TYPE VACUUM GAUGE FOR A VACUUM ATMOSPHERE OF AIR; RECORDING THE THERMOCOUPLE TYPE VACUUM GAUGE READING WHILE CONDUCTING THE DRYING OPERATION; SIMULTANEOUSLY RECORDING THE IONIZATION TYPE VACUUM GAUGE READING; AND APPLYING ADDITIONAL HEAT AND VACUUM TO THE VACUUM CHAMBER WHEN THE THERMOCOUPLE TYPE VACUUM GAUGE READING AND THE IONIZATION TYPE VACUUM GAUGE READING ARE ESSENTIALLY THE SAME, AT WHICH TIME THE MAJOR PORTION OF THE MOISTURE HAS BEEN REMOVED FROM THE MATERIAL BEING DRIED AND THE VACUUM CHAMBER ATMOSPHERE IS SUBSTANTIALLY ALL AIR.
Claim 2
Independent Claim 150 words
A METHOD OF DRYING A TEMPERATURE SENSITIVE MATERIAL IN A VACUUM CHAMBER HAVING IN COMMUNICATION THEREWITH A THERMOCOUPLE TYPE VACUUM GAUGE AND AN IONIZATION TYPE VACUUM GAUGE, COMPRISING THE STEPS OF: FREEZING THE MATERIAL; PLACING THE FROZEN MATERIAL IN THE VACUUM CHAMBER; APPLYING HEAT AND VACUUM TO THE VACUUM CHAMBER TO REMOVE MOISTURE FROM THE MATERIAL BEING DRIED; CALIBRATING THE THERMOCOUPLE TYPE VACUUM GAUGE AND THE IONIZATION TYPE VACUUM GAUGE FOR A VACUUM ATMOSPHERE OF AIR; RECORDING THE THERMOCOUPLE TYPE VACUUM GAUGE READING WHILE CONDUCTING THE DRYING OPERATION; SIMULTANEOUSLY RECORDING THE IONIZATION TYPE VACUUM GAUGE READING; AND APPLYING ADDITIONAL HEAT AND VACUUM TO THE VACUUM CHAMBER WHEN THE THERMOCOUPLE TYPE VACUUM GAUGE READING AND THE IONIZATION TYPE VACUUM GAUGE READING ARE ESSENTIALLY THE SAME, AT WHICH TIME THE MAJOR PORTION OF THE MOISTURE HAS BEEN REMOVED FROM THE MATERIAL BEING DRIED AND THE VACUUM CHAMBER ATMOSPHERE IS SUBSTANTIALLY ALL AIR.

References Cited (Backward Citations)

US2994132A Cited
US3020645A Cited
US3078586A Cited
US3192643A Cited
US3178829A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1969-07-11 1970-01-10 1970-07-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1973-07-11 1974-01-10 1974-07-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1977-07-11 1978-01-10 1978-07-12 $7700.00 Window Closed / Lapsed

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