Patent ID: 6521321
Filing Date: 2003-02-18
Classification: B01D,B32B,D04H,Y10S,Y10T

Abstract:
A filter media for filtering fluids; said filter media including:(a) a first filter media arrangement comprising a multi-layer composite and including at least first, second, third and fourth layers of fine fiber material therein: (i) said first layer of fine fiber material: (A) having an average fiber diameter of no greater than 5 microns; and, (B) having a first efficiency, on its own, for 0.78 micron particles of no greater than 25.5%; (ii) said second layer of fine fiber material: (A) having an average fiber diameter of no greater than 5 microns; and, (B) having a second efficiency, on its own, for 0.78 micron particles of no greater than 25.5%; (iii) said third layer of fine fiber material: (A) having an average fiber diameter of no greater than 5 microns; (B) having a third efficiency, on its own, for 0.78 micron particles of no greater than 54.5%; and (C) being positioned within said multi-layer composite with the second layer of fine fiber material between the third layer of fine fiber material and the first layer of fine fiber material; and (iv) said fourth layer of fine fiber material: (A) having an average fiber diameter of no greater than 5 microns; (B) having a fourth efficiency, on its own, for 0.78 micron particles; of no greater than 54.5%; and, (C) being positioned within said multi-layer composite with the third layer of fine fiber material between the fourth layer of fine fiber material and the second layer of fine fiber material; and (b) a first fibrous spacing layer positioned between the first and second layers of fine fiber material; the first fibrous spacing layer having an efficiency, on its own, for 0.78 micron particles, of no greater than 10%; (c) a second fibrous spacing layer positioned between the second and third layers of fine fiber material; the second fibrous spacing layer having an efficiency, on its own, for 0.78 micron particles of no greater than 10%; (d) a third fibrous spacing layer positioned between the third and fourth layers of fine fiber material, the third spacing layer having an efficiency, on its own, for 0.78 micron particles of no greater than 10%; (e) the first layer of fine fiber material being spaced from the second layer of fine fiber material by a distance of no greater than 254 microns; (f) the second layer of fine fiber material being spaced from the third layer of fine fiber material by a distance of no greater than 254 microns; (g) the third layer of fine fiber material being spaced from the fourth layer of fine fiber material by a distance of no greater than 254 microns; and (h) the first filter media arrangement having an overall efficiency, for 0.78 micron particles, of at least 40%.