Process for melt spinning and orienting polystyrene filaments

Claim 1

A PROCESS FOR THE ORIENTATION OF EXTRUDED POLYSTYRENE MONOFILAMENTS AND THE LIKE COMPRISING EMERGING MELTED UNORIENTED POLYSTYRENE MONOFILAMENTS AND THE LIKE FROM AN EXTRUSION DIE HEAD AND BEINGING SAID UNORIENTED MONOFILAMENTS INTO CONTACT WITH AT LEAST ONE DRIVEN COOLING ROLLER HEATED TO A TEMPERATURE IN THE RANGE OF 210 TO 330* F. WHILE MAINTAINING MONOFILAMENT-ROLLER CONTACT FOR A SUFFICIENT PERIOD OF TIME TO COOL SAID UNORIENTED MONOFILAMENTS TO ORIENTATION TEMPERATURE IN THE RANGE OF 210 TO 330* F., MAINTAINING A SUFFICIENTLY INSULATED ZONE THROUGH WHICH SAID MONOFILAMENTS PASS WHILE BEING COOLED TO AND WHILE AT ORIENTATION TEMPERATURE TO CONTROL HEAT LOSS FROM SAID MONOFILAMENTS TO PREVENT COOLING THEREOF BELOW ORIENTATION TEMPERATURE, MAINTAINING THE MONOFILAMENTS IN AN UNORIENTED STATE WHILE THEY ARE BEING COOLED TO ORIENTATION TEMPERATURE BY MAINTAINING SUFFICIENT MONOFILAMENT-ROLLER FRICTIONAL CONTACT SO THAT THE MONOFILAMENTS IN CONTACT WITH A COOLING ROLLER MOVE AT SUBSTANTIALLY THE SAME SURFACE SPEED AS SAID COOLING ROLLER TO PREVENT MONOFILAMENT ROLLER SLIPPAGE PRIOR TO ORIENTATION, AND APPLYING A SUFFICIENT ORIENTATION TENSIONING FORCE TO SAID MONOFILAMENTS, AFTER THEY HAVE BEEN COOLED TO AND WHILE AT ORIENTATION TEMPERATURE TO STRETCH SAID MONOFILAMENTS TO A DEGREE SUFFICIENT TO PRODUCE ORIENTED MONOFILAMENTS.