Patent ID: 9702060
Date: 2017-07-11
CPC Classifications: D01D,D01F,D04H,D10B,Y10T

Claim:
1. A process for producing spunbond fibers consisting essentially of: providing a polypropylene having a melt flow rate (230/2.16) of from 10 to 30 dg/min; melt blending the polypropylene with a visbreaking agent such that the resulting melt flow rate of the visbroken polypropylene is from 50 to 100 dg/min, wherein the visbroken polypropylene has a M melt extruding the visbroken polypropylene through a die block such that filaments of the visbroken polypropylene being produced are exposed to a cabin pressure of from 4500 to 7000 Pa, wherein the throughput of the visbroken polypropylene in forming filaments is greater than 200 kg/hour; and forming fibers of from less than 6.00 denier; wherein the pressure inside the die block ranges from 35 to 45 bar (3500 to 4500 kPa).