The present invention relates to a non-woven fabric for a non-woven air filtering substrate and an ADL substrate of fibre-based three-dimensional multi-layer structure, comprising at least 4 layers arranged one above another, arranged securely, wherein there is a first, upper layer in contact with the flow to be treated, which comprises fibres of a fineness ranging from 6 to 20 dtex and lengths ranging from 32 to 80 mm, and wherein the remaining layers comprise fibres of a fineness ranging from 0.6 to 10 dtex and lengths ranging from 12 to 64 mm. The present invention also relates to a method for producing the non-woven fabric that is the subject matter of the invention and also to the use thereof for preparing sanitary products or filters.