US 12,252,826 B2
Methods of saturating nonwoven fabrics with liquid and the making of electret thereof
Peter Ping-Yi Tsai, Knoxville, TN (US)
Assigned to University of Tennessee Research Foundation, Knoxville, TN (US)
Appl. No. 17/056,276
Filed by University of Tennessee Research Foundation, Knoxville, TN (US)
PCT Filed May 17, 2019, PCT No. PCT/US2019/032935
§ 371(c)(1), (2) Date Nov. 17, 2020,
PCT Pub. No. WO2019/222668, PCT Pub. Date Nov. 21, 2019.
Claims priority of provisional application 62/672,984, filed on May 17, 2018.
Prior Publication US 2021/0262134 A1, Aug. 26, 2021
Int. Cl. D06B 5/08 (2006.01); D06B 1/02 (2006.01); D06B 15/04 (2006.01); H01G 7/02 (2006.01)
CPC D06B 5/08 (2013.01) [D06B 1/02 (2013.01); D06B 15/04 (2013.01); H01G 7/023 (2013.01); Y10T 29/49226 (2015.01)] 10 Claims
OG exemplary drawing
 
1. A method of making an electret, the method comprising:
(a) providing a sheet comprising a nonwoven web of thermoplastic fibers;
(b) passing the sheet under a solid roller wherein the top surface of the sheet is in contact with the solid roller while simultaneously impinging the bottom surface of the sheet with one or more jets of water, thereby saturating the sheet with water to provide a saturated sheet; and
(c) transporting the saturated sheet away from the solid roller and the one or more jets of water to a position over an opening of a vacuum chamber and removing the water from the saturated sheet via suction to provide a charge, thereby providing an electret.