Process for producing polyethylene monofilaments

Claim 1

IN A PROCESS FOR THE PRODUCTION OF A MONOFILAMENT FROM HOT POLYETHYLENE WHEREIN POLYETHYLENE IS EXTRUDED AS A MOLTEN MASS THROUGH A DIE TO PRODUCE A MONOFILAMENT AND THEN COOLED WITH WATER HAVING A TEMPERATURE HIGH ENOUGH SO AS TO SLOWLY COOL THE MONOFILAMENT AND THEREBY PREVENT THE FORMATION OF SHRINK BUBBLES BEING SUCH AS TO CAUSE LOCALIZED BOILING OF THE WATER AT THE RELATIVE TEMPERATURE OF THE WATER AND MONOFILAMENT THE AREA OF IMMERSION OF THE MONOFILAMENT IN THE WATER RESULTING IN BOIL MARKS FORMING ON THE MONOFILAMENT, THE IMPROVEMENT WHICH COMPRISES COOLING THE MONOFILAMENT WITH AIR AFTER THE MONOFILAMENT LEAVES THE DIE BUT BEFORE COOLING THE MONOFILAMENT WITH WATER BY DIRECTING A FLOW OF AIR GENERALLY TRANSVERSELY TO THE MONOFILAMENT AT A LOW VELOCITY SO AS NOT TO PRODUCE VIBRATIONS IN THE MONOFILAMENT, THE SURFACE COOLING WITH AIR PREVENTING LOCALIZED BOILING OF THE WATER BY THE FILAMENT THAT RESULTS IN BOIL MARKS ON THE FILAMENT.