| 20100032869 | Molded Filter - The invention provides a moulded micro-fibrous filter in which micro-fibres are held together by a binder, wherein the binder is a cured thermosetting acrylate resin. In a further aspect the invention provides an aqueous fibre slurry for use in moulding filter media, wherein said slurry comprises additionally a binder resin in an amount effective, after moulding said filter and curing, to act as binder for the media In a yet further aspect, the invention provides a method of moulding a filter, which comprises the steps of: (a) forming a slurry of fibers as aforesaid; (b) introducing the slurry under pressure into the top of an annular molding space defined between a central core, a vertical cylindrical screen spaced from and outward of said core and a support defining a lower boundary for the molding space so that a mass of fibers becomes compacted on the screen and liquid is discharged from the molding space through the screen; (c) progressively increasing the height of the effective open area of the cylindrical screen by moving upwardly a sleeve in sliding contact with the cylindrical screen at a rate substantially equal to the rate at which the height of the mass of fibers increases above the support; (d) removing the resulting tubular mass of fibers from the molding space; and (e) drying the tubular mass and curing binder resin to form said filter. The acrylate binder resin is compatible with the e.g. acidic conditions needed to stabilize the resin, can form part of the fiber slurry used for molding the filter, and after filter formation and drainage can be cured by heat to complete formation of the molded filter element. | 02-11-2010 |
