Electrostatic field enhancing process and apparatus for improved web pinning
US5296172A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 1992 |
| Grant date | Mar 22, 1994 |
| Priority date | — |
| Expiry date | Jul 31, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2995/001
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Process and apparatus for improving web pinning and uniformity in a fibrous web forming operation. The improvements are achieved by imposing an auxiliary electrostatic field above the fibrous web as it is pinned along a moving collection surface. An auxiliary electrostatic field enhancing plate is positioned above the web and collection surface and downstream of the laydown position where the web initially is deposited on the collection surface. The plate enhances the electrostatic field in the region above the collection surface and thereby increases the web pinning forces. When the invention is applied to a flash-spinning process where trifluorochloromethane is used as the fluid medium, an auxiliary electrostatic field of between about 2 and 80 kV/cm, preferably between about 10 and 60 kV/cm, is applied by the plate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.