Patent ID: 9592465
Date: 2017-03-14
CPC Classifications: B01D,F02M

Claim:
1. A filter material for an air filter, comprising: a substrate layer on an inflow side and a fine-fibre layer on an outflow side relative to a flow direction; a connection region arranged between the substrate layer and the fine-fibre layer, the substrate layer, connection region and fine-fibre layer including pores having an aggregate degressive pore size with respect to the flow direction; wherein a combined thickness of the substrate layer, connection region and fine-fibre layer is at least 0.35 mm; wherein the substrate layer includes a cellulose material and has an impregnation of resin disposed along the inflow side; the resin amounting to approximately 22% by mass of the substrate layer; wherein the connection region is composed of at least one of a composite of the substrate layer and the fine-fibre layer and an additional material, and wherein the connection region has a degressive pore size along the flow direction; and wherein the substrate layer has an extent along the flow direction approaching the connection region absent the impregnation of the resin.