Abstract: An apparatus for manufacturing a filtering medium in sheet form, comprising at least one first continuous machine, adapted for manufacturing paper and the like and suitable to form at least one first web on a first conveyor, and at least one second continuous machine also adapted for manufacturing paper and the like and suitable to form at least one second web on at least one second conveyor, the at least one second conveyor being arranged so as to make the at least one second web rest by gravity on the at least one first web, and at least one of the first and second continuous machines being suitable to form a web which is not uniformly distributed.

Abstract: A filtering medium in the form of a sheet of paper for filters for fluids in general, wherein the paper impregnating agent is an aqueous emulsion of:an anionic aqueous disperse system of a copolymer based on n-butylacrylate-styrene.Dosage: 20%-50% by weight;an aqueous disperse system of a copolymer which can be thermally cross-linked and is based on butyl acrylate and acrylonitrile.Dosage: 30%-70% by weight;an aqueous disperse system of melamine-formaldehyde resin, etherified with methanol.Dosage: 1%-20% by weight;an aqueous disperse system of fluorocarbon resin.Dosage: 5%-40% by weight;an aqueous emulsion of organopolysiloxane.Dosage: 0%-15% by weight.