Patent ID: 8308834

Claim:
A composite filter media structure comprising: a base substrate comprising a nonwoven synthetic fabric formed from a plurality of fibers with a spunbond process, said base substrate having a minimum filtration efficiency of about 50% capture of particles having a size of about 0.3 μm to about 0.4 μm, measured in accordance with ASHRAE 52.2-1999 test procedure, said base substrate having a resistance less than about 2.5 mm of water, measured in accordance with EN-1822 (1998), said nonwoven synthetic fabric comprises a bond area pattern comprising a plurality of substantially parallel discontinuous lines of bond area, each discontinuous line of bond area comprising a plurality of linear lines of bond area arranged end to end with a non bond area between each linear line of bond area; and a nanofiber layer deposited on one side of said base substrate, said composite filter media structure having a minimum filtration efficiency of about 75% capture of particles having a size of about 0.3 μm to about 0.4 μm, measured in accordance with ASHRAE 52.2-1999 test procedure.