US3689608A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for forming a nonwoven web
Assignee: EIDP Inc
•
Filing: 1970-06-10
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Granted: 1972-09-05
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Expires: 1990-06-10
Abstract
Abstract A process for spreading, electrostatically charging, and forwarding a fibrous web concomitantly formed with a vapor blast. The web is charged by passing it through a highly ionized zone created by a corona discharge between an ion gun and a target plate. The electrical potential between the ion gun and target plate causes current to flow which is sufficient to deposit a charge on the web which is preferably 75 to 100 percent of the maximum sustainable charge, but low enough to avoid loss of web charge through secondary corona discharge between the target plate and the web.
Inventors
- 👤 Herbert John Hollberg
- 👤 John Edward Owens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:37
CPC Classifications
D; D04; D04H; D04H3/00; D04H3/08; D04H3/16; D01; D01D; D01D5/00; D01D5/04; D01D5/11; H; H01; H01T; H01T19/00; H01T19/04
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
21 words
The process of claim 1 wherein said gaseous atmosphere is at least about 70 percent gaseous solvent, the remainder being air.
Claim 2
Dependent Claim
11 words
The process of claim 2 wherein said gaseous solvent is trichlorofluoromethane.
Claim 3
Dependent Claim
27 words
The process of claim 1 including the step of applying a potential on said collecting surface which is opposite in polarity to the charge on the web.
Claim 4
Dependent Claim
18 words
The process of claim 1, said current being maintained at a level of from about 225- 325 microamperes.
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) | 1975-09-05 | 1976-03-06 | 1976-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-05 | 1980-03-06 | 1980-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-05 | 1984-03-06 | 1984-09-05 | $7700.00 | Window Closed / Lapsed |