| 摘要 |
<p>#CMT# #/CMT# The first layer (101) is a net, perforated sheet or perforated fleece. Its air permeability is at least 10000 liters / (m 2>s). A first fibrous layer (102) comprises artificial fibers and/or plant fibers. This is fastened to one side of the first layer. The net is extruded or woven. The weight of the first layer is preferably 7-20 g/m 2>. Its thickness is preferably 0.15 - 0.8 mm. Its mean perforated cross sectional area is preferably 5 - 30 mm 2> and/or the air permeability is preferably 13000 liters/(m 2>s). The net mesh width is 2-30 mm. Fibers in the fibrous layer have a fineness of 5-10 dtex. #CMT# : #/CMT# An independent claim IS INCLUDED FOR the method of manufacture. #CMT#USE : #/CMT# A vacuum cleaner filter bag. #CMT#ADVANTAGE : #/CMT# This vacuum cleaner filter bag combines desirably-high mechanical stability, with a low tendency to blockage. The bag is disposable. Bonding is e.g. by calendering, which leaves the layers immovable with respect to each other. Diverse alternative structures and raw materials may be used; these are discussed further in the disclosure. Further layers (103, 104) may be included. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a first example of the filter medium in cross section. 101 : first layer 102 : first fibrous layer 103 : second fibrous layer 104 : further fibrous layer.</p> |
