Patent ID: 8114238
Filing Date: 2012-02-14
Classification: B01D,B29C,B29L

Abstract:
1. A method for producing a tight joint between a thermally fusible multi-layer synthetic resin material and a fluid-permeable filter medium, said method comprising: pleating a sheet of said filter medium and arranging into an annular ring having two opposing ends; forming a unitary multi-layer synthetic resin end disk by injection molding, said multi-layer end disk including a synthetic resin carrier layer and synthetic resin fusion layer arranged on said carrier layer, said fusion layer having a higher thermal absorption capacity than said carrier layer, said fusion layer arranged onto and abutting said carrier layer, wherein said end disk is sized to extend over said opposing end of said filter medium, said fusion layer sized and positioned to be received against said filter medium ends, applying infrared radiation to said and fusion layer of said multi-layer synthetic resin end disk to heat said layer: then selectively melting said fusion layer of said end disk from a solid state to a melted state by said infrared radiation without melting said carrier layer of said end disk; then contacting said melted fusion layer of said end disk against said filter medium end; then cooling and solidifying said melted fusion layer, wherein said solidifying fuses said melted fusion layer onto said filter medium to form said tight joint; wherein the fusion layer and carrier layer each contain at least a pigment, wherein the pigment in the fusion layer is a different pigment from the pigment in the carrier layer, wherein the pigment in the fusion layer is visually indistinguishable from the pigment in the carrier layer, wherein the pigment in the fusion layer absorbs heat differently than the pigment in the carrier layer.