METHOD FOR PRODUCTION OF NONWOVEN FILTER MEDIUM Russian patent published in 1995 - IPC

FIELD: production of nonwoven filter media. SUBSTANCE: fiber-forming solution is sprayed in high-voltage field and fibers are deposited on conveying electrodes in layers. The first layer is deposited on glossy surface of depositing conveying electrode at voltage of 70-80 kV with surface density of 30-250 g/sq.m with fibers 8-40 mcm in diameter. The second layer is applied to surface of the first at voltage of 90-110 kV and surface density of 15-35 g/sq. m with fibers 0.1-8 mcm in diameter. The third layer is applied to the second layer at voltage of 70-80 kV, surface density of 30-250 g/sq.m with fibers 8-40 mcm in diameter and ratio of layer thickness of (2-10):1: (2-10). EFFECT: higher efficiency. 1 dwg