Patent ID: 8052906

Claim:
A process for making a synthetic melt spun polyamide filament comprising the steps of: supplying polyamide polymer with an RV of 36 to 38 to a solid phase polycondensation apparatus; humidifying a purge gas with water vapor; supplying said purge gas to the solid phase polycondensation apparatus at a flow rate in the range of about 2 to about 3 kg/hour per kg of polymer per hour; treating the polyamide polymer in the solid phase polycondensation apparatus with the purge gas at a solid phase polycondensation system pressure of about 110 to about 120 kPascal; conveying the treated polyamide polymer to a melt extrusion apparatus; melting the polyamide polymer in the melt extrusion apparatus; extruding the melted polyamide polymer through a spinneret plate; and forming at least one continuous filament of polyamide polymer with a yarn RV of about 51 to about 54.