FILTERING MATERIAL Russian patent published in 1995 - IPC

FIELD: filtering materials. SUBSTANCE: filtering material has air permeable substrata and a layer of electrically charged ultra-thin polymer fibers. The material has additional filtering protective skeleton-like layer of polymer fiber of 8 - 40 mcm diameter and 30-110 g/m² surface density with relation between layer thickness of ultra-thin polymer fibers and additional layer thickness within 1:0.8 to 1:3. Besides, the additional layer has polymer fibers produced of solution of perchlorvinyl resin and polystyrene, or styrene copolymer, with relation of components (per cent by weight) as follows: 3 - 6 perchlorvinyl resin, 3 - 6 polystyrene or styrene copolymer, 85 - 92 dichloroethane, 0.4 - 3 ethyl alcohol, the balance being radon ammonium or bromine tetraethyl ammonium. EFFECT: highly effective filtering material. 2 cl