Method of charging electret filter media
AssigneeMinnesota Mining and Manufacturing Company
InventorsSeyed A. Angadjivand, Marvin E. Jones, Daniel E. Meyer
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Abstract
A method of charging a nonwoven web of thermoplastic microfibers to provide electret filter media is provided. The method includes impinging on a nonwoven web of thermoplastic nonconductive microfibers capable of having a high quantity of trapped charge jets of water or a stream of water droplets at a pressure sufficient to provide the web with filtration enhancing electret charge and drying said web.
Claims13
A method of charging a nonwoven web of thermoplastic microfibers to provide electret filter media comprising (1) impinging on a nonwoven web of thermoplastic nonconductive microfibers which have a resistivity greater than 10.sup.16 ohm cm and are capable of having a high quantity of trapped charge, jets of water or a stream of water droplets at a pressure sufficient to provide the web with filtration enhancing electret charge and (2) drying said web.
Dependencies are inferred from the claim text.