Patent ID: 8052878

Claim:
A method for filtering out foreign particles from a cooling lubricant used in a process of machining a workpiece, the method comprising: providing an inherently stable, flow-porous filter element which comprises: a porous main body made of joined plastics particles and having an afflux surface; and a porous coating on the afflux surface for surface filtration comprising a composite including: first component particles and/or fibres, second component anti-adhesion particles to mitigate the adhesion of filtered out material to the porous coating and to facilitate cleaning of the filter element, with the first component particles and/or fibres and the second component particles being mixed in the porous coating, a solidified inorganic binder, and a set adhesive, wherein the solidified inorganic binder and the set adhesive bind the first component particles and/or fibres and the second component particles to each other and to the porous main body; and passing the flow of cooling lubricant first through the porous coating and thereafter through the porous main body of the filter element.