Abstract: The invention concerns a filter material characterized in that it is impregnated with an amphiphilic substance or with a hydrophilic and a hydrophobic substance to control the water wettability and water absorption.

Abstract: The invention concerns a filter material particularly useful in the manufacture of tea bags, coffee bags, coffee filters and the like. The filter material includes an at least two layer non-woven substrate material wherein the two layers are essentially planar and superimposed, one layer is composed of natural fibers and one layer is composed of synthetic fibers. The synthetic fiber layer includes a plurality of individual plastic fibers which are deposited in a heated state on the natural fiber layer. The plastic fibers fuse with each other and also fuse with the natural fibers of the other layer. The filter material provides the particular advantage, due to the deposition of the individual plastic fibers on the natural fibers, of covering or closing a large number of pores or ducts in the natural fiber layer.