Spunbond nonwoven fabric with improved opening quality and no hazardous residue, manufacturing method thereof and manufacturing apparatus thereof

Abstract

The present invention relates to a spunbond nonwoven fabric with improved opening quality and no hazardous residue, a manufacturing method thereof, and a manufacturing apparatus thereof. The method for manufacturing a spunbond nonwoven fabric according to the present invention includes a step of allowing the continuous filament bundle to collide with a metal member containing bismuth (Bi) or a bismuth alloy to obtain filaments opened by frictional charging.

1 . A method for manufacturing a spunbond nonwoven fabric, the method comprising the steps of:
 melt-spinning a thermoplastic resin to obtain a continuous filament bundle;   allowing the continuous filament bundle to collide with a metal member containing bismuth (Bi) or a bismuth alloy to obtain filaments opened by frictional charging; and   converging the opened filaments on a continuous conveyor net to form a fiber web.   
     
     
         2 . The method for manufacturing a spunbond nonwoven fabric according to  claim 1 , wherein the bismuth alloy contains 10% by weight or more of bismuth based on the weight of the bismuth alloy. 
     
     
         3 . The method for manufacturing a spunbond nonwoven fabric according to  claim 1 , wherein the bismuth alloy comprises at least one metal selected from the group consisting of copper (Cu), zinc (Zn), tin (Sn), aluminum (Al), molybdenum (Mo), and titanium (Ti). 
     
     
         4 . The method for manufacturing a spunbond nonwoven fabric according to  claim 1 , wherein the continuous filament bundle collides with the metal member at a linear velocity of 4000 m/min to 6000 m/min and a mass flow rate of 2.0 kg/h to 8.0 kg/h per nozzle that jets the continuous filament bundle. 
     
     
         5 . The method for manufacturing a spunbond nonwoven fabric according to  claim 1 , wherein the opened filaments have a charge generation amount by the frictional charging (a value measured by a Faraday cage method) of −3500 nC/s to −500 nC/s. 
     
     
         6 . The method for manufacturing a spunbond nonwoven fabric according to  claim 1 , wherein the opened filaments are converged on the continuous conveyor net with an opening width of 500 mm or more under conditions where the rotation angle range of the nozzle for jetting the filament bundle is −15±5° to +15±5° and the reciprocating speed of the nozzle is 3 counters/s to 12 counters/s (wherein the opening width means the maximum width based on the moving direction of the opened filaments converged on the continuous conveyor net). 
     
     
         7 . The method for manufacturing a spunbond nonwoven fabric according to  claim 1 , wherein the thermoplastic resin has a melting point of 200° C. or more, and the thermoplastic resin is at least one resin selected from the group consisting of polyester, polyamide, polyolefin, and polyphenylene sulfide. 
     
     
         8 . The method for manufacturing a spunbond nonwoven fabric according to  claim 1 , wherein the thermoplastic resin is at least one resin selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, polycyclohexane terephthalate, polyethylene naphthalate, nylon, polyethylene, polypropylene, polybutylene, and polyphenylene sulfide. 
     
     
         9 . An apparatus for manufacturing a spunbond nonwoven fabric, the apparatus comprising:
 a plurality of nozzle units configured and arranged so as to discharge a continuous filament bundle;   a collision unit that is adjacent to each of the nozzle units at a position for colliding with the continuous filament bundle jetted by the nozzle units; and   a continuous conveyor net that collects and conveys filaments opened by frictional charging with the collision unit,   wherein the collision unit comprises a collision surface that is a metal member containing bismuth (Bi) or a bismuth alloy.   
     
     
         10 . The apparatus for manufacturing a spunbond nonwoven fabric according to  claim 9 , wherein the bismuth alloy contains 10% by weight or more of bismuth based on the weight of the bismuth alloy. 
     
     
         11 . The apparatus for manufacturing a spunbond nonwoven fabric according to  claim 9 , wherein the bismuth alloy comprises at least one metal selected from the group consisting of copper (Cu), zinc (Zn), tin (Sn), aluminum (Al), molybdenum (Mo), and titanium (Ti). 
     
     
         12 . The apparatus for manufacturing a spunbond nonwoven fabric according to  claim 9 , wherein the nozzle unit comprises a jet nozzle that discharges the continuous filament bundle, and
 the jet nozzle is connected to a step motor shaft and is controlled at a nozzle rotation angle ranging from −15±5° to +15±5° and a nozzle reciprocating speed of 3 counters/s to 12 counters/s.   
     
     
         13 . A spunbond nonwoven fabric which is obtained by the method according to  claim 1 , comprises a fiber web containing thermoplastic resin filaments, and has a residual amount of bismuth (Bi) of 0.01 ppmw to 10.0 ppmw. 
     
     
         14 . The spunbond nonwoven fabric according to  claim 13 , wherein the spunbond nonwoven fabric has a residual amount of lead (Pb) of 0.1 ppmw or less. 
     
     
         15 . The spunbond nonwoven fabric according to  claim 13 , wherein the spunbond nonwoven fabric has a quality index (Q) of 350 or less, which is defined by the following Equation 1:
   Quality index ( Q )=SD/OD  [Equation 1]
   and in the above Equation 1,   OD is the optical density of the spunbond nonwoven fabric measured using a formation tester, and   SD is the standard deviation of OD (optical density).   
     
     
         16 . The spunbond nonwoven fabric according to  claim 13 , wherein the thermoplastic resin has a melting point of 200° C. or more, and the thermoplastic resin is at least one resin selected from the group consisting of polyester, polyamide, polyolefin, and polyphenylene sulfide. 
     
     
         17 . The spunbond nonwoven fabric according to  claim 13  wherein the thermoplastic resin is at least one resin selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, polycyclohexane terephthalate, polyethylene naphthalate, nylon, polyethylene, polypropylene, polybutylene, and polyphenylene sulfide.