US3852392A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of removing plasticizer mist from air
Assignee: Hexion Inc
•
Filing: 1972-12-18
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Granted: 1974-12-03
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Expires: 1992-12-18
Abstract
Abstract Hot polyvinyl chloride film is blown in a confined area so as to eliminate escape of plasticizer mist. The plasticizer mist generated is passed through a suitable scrubber, filter or other such known device to remove the plasticizer. The heated air component of the mist, free of plasticizer, is then returned to the process building to recover the heat content, or discharged to the atmosphere as desired.
Inventors
- 👤 W Davis
- 👤 J Golner
- 👤 S Feinstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:33
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/03; B29C48/09; B29C48/10; B29C48/001; B29C48/0018; B29C48/0019; B29C48/355; Y; Y02; Y02P; Y02P70/00; Y02P70/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
130 words
IN A BLOWN TUBE METHOD FOR MAKING PLASTICIZED POLYVINYL CHLORIDE FILM WHEREIN MOLTEN PLASTICIZED THERMOPLASTIC IS EXTRUDED IN THE FORM OF A SEAMLESS TUBING WITH THE TUBING BEING FLATTENED AT A POINT SPACED FROM THE POINT OF EXTRUSION AND INFLATED TO A PREDETERMINED DIAMETER INTERMEDIATE THE POINT OF EXTRUSION AND THE POINT OF THE TUBING WHERE PLASTICIZER MIST IS NO LONGER RELEASED IN ANY SUBSTANTIAL QUANTITY FROM THE SURFACE OF THE FILM; THE EXTERIOF SURFACE OF TUBING BEING WHOLLY ENVELOPED IN THE VICINITY OF THE POINT OF EXTRUSION WITH A COOLING MEDIUM OF CHILLED GAS, THE CHILLED GAS CIRCULATED THROUGH THE ENNCLOSURE SUCH THAT THE CHILLED GAS WHOLLY ENVELOPES THE EXTERIOR SURFACE OF THE MOLTEN PLASTIC BEING EXTRUDED TO COOL THE PLASTIC TO ITS SOLIDIFICATION POINT AND TO PICK UP
Claim 2
Dependent Claim
130 words
IN A BLOWN TUBE METHOD FOR MAKING PLASTICIZED POLYVINYL CHLORIDE FILM WHEREIN MOLTEN PLASTICIZED THERMOPLASTIC IS EXTRUDED IN THE FORM OF A SEAMLESS TUBING WITH THE TUBING BEING FLATTENED AT A POINT SPACED FROM THE POINT OF EXTRUSION AND INFLATED TO A PREDETERMINED DIAMETER INTERMEDIATE THE POINT OF EXTRUSION AND THE POINT OF THE TUBING WHERE PLASTICIZER MIST IS NO LONGER RELEASED IN ANY SUBSTANTIAL QUANTITY FROM THE SURFACE OF THE FILM; THE EXTERIOF SURFACE OF TUBING BEING WHOLLY ENVELOPED IN THE VICINITY OF THE POINT OF EXTRUSION WITH A COOLING MEDIUM OF CHILLED GAS, THE CHILLED GAS CIRCULATED THROUGH THE ENNCLOSURE SUCH THAT THE CHILLED GAS WHOLLY ENVELOPES THE EXTERIOR SURFACE OF THE MOLTEN PLASTIC BEING EXTRUDED TO COOL THE PLASTIC TO ITS SOLIDIFICATION POINT AND TO PICK UP
Claim 3
Dependent Claim
14 words
The method of claim 1, wherein the confined area is maintained at subatmospheric pressure.
Claim 4
Dependent Claim
23 words
The method of claim 2, wherein sufficient air is allowed to enter the confined area from the atmosphere to prevent substantial pressure fluctuations.
Claim 5
Dependent Claim
27 words
The method of claim 3, wherein air is allowed to enter the confined area through an opening surrounding the source of the cooling medium of chilled gas.
Claim 6
Dependent Claim
18 words
The method of claim 4, wherein the opening has a width of from 1/4 th to 3 inches.
References Cited (Backward Citations)
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US3061876A
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US3331901A
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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) | 1977-12-02 | 1978-06-03 | 1978-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-02 | 1982-06-03 | 1982-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-02 | 1986-06-03 | 1986-12-03 | $7700.00 | Window Closed / Lapsed |