Air filtration medium with improved dust loading capacity and improved resistance to high humidity environment
AssigneeE. I. Du Pont de Nemours and Company
InventorsCheng-Hang Chi, Hyun Sung Lim, Lu Zhang
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Abstract
A filtration medium is disclosed for use in air filters used in heating, ventilating and air conditioning systems. The medium contains at least one nanofiber layer of fibers having diameters less than 1 μm and at least one upstream layer, the medium having sufficient holding capacity for dust particles that efficiency loss and pressure loss across the medium are minimized during use.
Claims96
A filter media comprising a nanofiber web with a number average fiber diameter of less than one micron and an upstream microfiber web layer in a face to face relationship with the nanofiber web where the ratio of the mean flow pore size of the microfiber web layer to that of the nanofiber web is between about 1 to about 10.
A filter media comprising a nanofiber web with a number average fiber diameter of less than one micron and an upstream microfiber web layer in a face to face relationship with the nanofiber web where the mean flow pore size of the microfiber web layer is between about 13 to about 40 microns.
A filter media comprising a nanofiber web with a number average fiber diameter of less than one micron and an upstream microfiber web layer in a face to face relationship with the nanofiber web where the ratio of the mean flow pore size of the microfiber web layer to a particle size is between about 50 and about 154 when the media has an efficiency of between 50% and 99.97% when impinged upon by particles of the particle size.
A method of filtering air comprising the step of passing the air through a media comprising a nanofiber web with a number average fiber diameter of less than one micron and an upstream microfiber web layer in a face to face relationship with the nanofiber web where the ratio of the mean flow pore size of the microfiber web layer to that of the nanofiber web is between about 1 to about 10.
A method of filtering air comprising the step of passing the air through a media comprising a nanofiber web with a number average fiber diameter of less than one micron and an upstream microfiber web layer in a face to face relationship with the nanofiber web where the mean flow pore size of the microfiber web layer is between about 12 to about 40 microns.
A method of filtering air comprising the step of passing the air through a media comprising a nanofiber web with a number average fiber diameter of less than one micron and an upstream microfiber web layer in a face to face relationship with the nanofiber web where the ratio of the mean flow pore size of the microfiber web layer to a particle size is between about 50 and about 154 when the media has an efficiency of between 50% and 99.97% when impinged upon by particles of the particle size.
Dependencies are inferred from the claim text.