US3299525A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carrier gas sublimation
Assignee: FMC Corp
•
Filing: 1964-06-29
•
Granted: 1967-01-24
•
Expires: 1984-06-29
Abstract
No abstract record available.
Inventors
- 👤 Thuse Erik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:12
CPC Classifications
A; A23; A23B; A23B2/00; A23B2/90; A23B2/92; F; F26; F26B; F26B5/00; F26B5/04; F26B5/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
146 words
THE METHOD OF FREEZE DRYING CELLULAR MATERIALS COMPRISING THE STEPS OF PLACING FROZEN CELLULAR MATERIALS IN A CHAMBER, SUPPLYING HEAT OF SUBLIMATION TO THE ICE CORE OF THE FROZEN MATERIAL BY RADIATION AND CONDUCTION, REDUCING THE PARTIAL PRESSURE OF THE WATER VAPOR IN THE CHAMBER BELOW THE TRIPLE POINT PRESSURE BY CONDENSING THE WATER VAPOR SUBLIMED FROM THE FROZEN PRODUCT DIRECTLY IN THE CHAMBER, INITIATING THE CIRCULATION OF A DRY, HEATED, NON-OXIDIZING, HEAT CARRIER GAS THROUGH THE CHAMBER AND ACROSS THE MATERIALS AFTER A MAJORITY OF THE ICE CORE IN THE PRODUCT HAS SUBLIMED TO SWEEP AWAY WATER VAPOR AND INCREASE THE CONDUCTIVITY OF THE SHELL OF THE DRIED MATERIAL, PARTIALLY SHIELDING THE VAPOR CONDENSING ELEMENTS IN THE CHAMBER FROM THE CARRIER GAS, REMOVING WATER VAPOR ENTRAINED BY THE GAS, REHEATING THE GAS, AND RE-CIRCULATING THE GAS THROUGH THE CHAMBER UNTIL THE MATERIAL HAS FULLY DRIED.
Claim 2
Independent Claim
146 words
THE METHOD OF FREEZE DRYING CELLULAR MATERIALS COMPRISING THE STEPS OF PLACING FROZEN CELLULAR MATERIALS IN A CHAMBER, SUPPLYING HEAT OF SUBLIMATION TO THE ICE CORE OF THE FROZEN MATERIAL BY RADIATION AND CONDUCTION, REDUCING THE PARTIAL PRESSURE OF THE WATER VAPOR IN THE CHAMBER BELOW THE TRIPLE POINT PRESSURE BY CONDENSING THE WATER VAPOR SUBLIMED FROM THE FROZEN PRODUCT DIRECTLY IN THE CHAMBER, INITIATING THE CIRCULATION OF A DRY, HEATED, NON-OXIDIZING, HEAT CARRIER GAS THROUGH THE CHAMBER AND ACROSS THE MATERIALS AFTER A MAJORITY OF THE ICE CORE IN THE PRODUCT HAS SUBLIMED TO SWEEP AWAY WATER VAPOR AND INCREASE THE CONDUCTIVITY OF THE SHELL OF THE DRIED MATERIAL, PARTIALLY SHIELDING THE VAPOR CONDENSING ELEMENTS IN THE CHAMBER FROM THE CARRIER GAS, REMOVING WATER VAPOR ENTRAINED BY THE GAS, REHEATING THE GAS, AND RE-CIRCULATING THE GAS THROUGH THE CHAMBER UNTIL THE MATERIAL HAS FULLY DRIED.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-01-23 | 1970-07-25 | 1971-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-01-23 | 1974-07-25 | 1975-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-01-23 | 1978-07-25 | 1979-01-24 | $7700.00 | Window Closed / Lapsed |