Patent ID: 6136409
Filing Date: 2000-10-24
Classification: B01D,B32B,D04H,Y10T

Abstract:
A filter medium in the form of a laminate comprising a permeable nonwoven fabric comprising a multiplicity of individual fibers arranged as bundles, and adhered to one another, wherein at least numerically 50% of all the fibers that are present in the entire nonwoven fabric are present in the form of fiber bundles in which a plurality of individual fibers are bonded together, wherein said fiber bundles are arranged generally regularly through the thickness of said fabric and substantially in the same direction and wherein substantially all of said fiber bundles are arranged at a direction substantially within an angle in the range of about .+-.35 degrees with respect to said same direction bonded to an air permeable fibrous sheet having an air permeability of at least 5 cc/mm.sup.2 /sec.