| 摘要 |
PROBLEM TO BE SOLVED: To flatten a filter having a filler added thereto by passing a molten thermoplastic resin containing a filler specified in the standard deviation of a particle size through a filter specified the filler, filtering accuracy, the product of the diameter and basis wt. of metal fibers, the axial orientation of metal fibers, the voids of the filler and the flow resistance of air. SOLUTION: A thermoplastic resin containing a filler wherein an average particle size isδand the standard deviation thereof is 0.1δor more is melted using an extruder. This resin is passed through a filter wherein the filler and filtering accuracy satisfy formula I, the product of the diameter (d) and wt. basis (w) of metal fibers of the n-th layer satisfy formulae II, III, media composed of metal fibers of which the axes are oriented in the direction crossing the flow of the molten resin at a right angle and having voids of 35-90% are laminated and the flow resistance of air is 35mm H2 O or more to be filtered and subsequently emitted from a cap to be quenched to be molded into a sheet form. n is the number from the upstream side of the media constituting the filter. |
