Patent ID: 7942948

Claim:
A filter element comprising a first end cap, a second end cap, and a composite filter media structure, the composite filter media structure comprising: a base substrate comprising a nonwoven synthetic fabric formed from a plurality of bicomponent synthetic fibers with a spunbond process, said nonwoven synthetic fabric comprises a bond area of about 10% to about 14% of an area of said nonwoven fabric, said bond area pattern comprising a plurality of substantially parallel discontinuous lines of bond area, said base substrate having a minimum filtration efficiency of about 50%, measured in accordance with ASHRAE 52.2-1999 test procedure; and a nanofiber layer deposited on one side of said base substrate by an by electro-blown spinning process, said nanofiber layer comprising a plurality of nanofibers, said composite filter media structure having a minimum filtration efficiency of about 75%, measured in accordance with ASHRAE 52.2-1999 test procedure, said composite media structure further comprising a plurality of corrugations, said corrugations formed using opposing corrugating rollers at a temperature of about 90° C. to about 140° C.