US3595245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cigarette filter from polypropylene fibers
Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1968-08-14
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Granted: 1971-07-27
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Expires: 1988-08-14
Abstract
Abstract A roving of entangled and self-bonded fine fibers of polypropylene may be formed by a melt blown roving technique which comprises extruding the polypropylene through a die having the die openings in a circle into a gas stream to attenuate the extruded polypropylene into fibers and collecting the fibers as a tow. The roving or tow of polypropylene fibers is an aggregation of fiber loops which is essentially cylindrical in shape, made from essentially continuous fibers which are entangled and bonded to each other. The roving or tow may be cut as filters for cigarettes.
Inventors
- 👤 Robert R Buntin
- 👤 John W Harding
- 👤 James P Keller
- 👤 Vollie L Murdock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:04
CPC Classifications
A; A24; A24D; A24D3/00; A24D3/02; A24D3/0229; A24D3/0237; Y; Y10; Y10S; Y10S264/00; Y10S264/75
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
11 words
A roving according to claim 1 wherein the roving is cylindrical.
Claim 2
Dependent Claim
11 words
A roving according to claim 1 wherein said fibers are self-bonded.
Claim 3
Dependent Claim
11 words
A roving according to claim 1 wherein said fibers are polypropylene.
Claim 4
Dependent Claim
19 words
A roving according to claim 4 having a bulk density within the range of between 0.05 and 0.20 g./cc.
Claim 5
Dependent Claim
19 words
A roving according to claim 4 having a bulk density within the range of between 0.09 and 0.16 g./cc.
Claim 6
Dependent Claim
12 words
A roving according to claim 4 having a smooth, firm outer surface.
Claim 7
Dependent Claim
11 words
A roving according to claim 5 wherein the roving is cylindrical.
Claim 8
Dependent Claim
17 words
A roving according to claim 8 having a circumference within the range of 24 to 28 mm.
Claim 9
Dependent Claim
10 words
A cigarette filter made from the roving of claim 4.
Claim 10
Dependent Claim
10 words
A cigarette filter made from the roving of claim 9.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |