Multi-layer filter construction, use of such a multi-layer filter construction, dust filter bag, pockets filter bags, pleated filter, two-dimensional exhaust air filter and an air filter for motor vehicles

摘要

Multi-layer filter structure (e) for removing dust from the fluids in which in the direction of the inflow side and the outflow side a coarse dust filter layer (a), a fine dust filter layer (b) and a backing layer (c) are disposed successively, the fibre within the coarse dust filter layer (a) and the fine dust filter layer (b) has a gradient, wherein the fiber diameter of the coarse dust filter layer (a) and the fine dust filter layer (b) of the outflow side of the angle of attack - continuously decrease, and wherein the fiber diameter of the coarse dust filter layer (a) and the fine dust filter layer (b) in the region of the contacting surfaces is less than 20% distinguish.