Multi-layer filter material for a vacuum cleaner bag

摘要

The multi-layer filter material has a pre-separation layer (1), a dust storage layer (2), and a tensile strength increasing layer (3) that are arranged in upstream. The tensile strength increasing layer has two layers of spun-bonded non-woven fabrics (3.1,3.2) which are linearly connected to one another. The triangular, quadrangular or hexagonal patterns are formed in a section of a connecting line.