Polyamide multifilament and knitted lace manufactured using same

Abstract

A polyamide multifilament has a single-filament fineness of 0.8 dtex to 7 dtex, a strength of 7.5 cN/dtex to 8.5 cN/dtex, and a knot strength of 6.0 cN/dtex to 7.5 cN/dtex. The polyamide multifilament may have a tensile strength at 15% elongation of 6.1 cN/dtex to 7.5 cN/dtex. The polyamide multifilament may have a total fineness of 20 dtex to 44 dtex.

1 - 6 . (canceled) 
     
     
         7 . A polyamide multifilament having a single-filament fineness of 0.8 dtex to 7 dtex, a strength of 7.5 cN/dtex to 8.5 cN/dtex, and a knot strength of 6.0 cN/dtex to 7.5 cN/dtex. 
     
     
         8 . The polyamide multifilament according to  claim 7 , having a tensile strength at 15% elongation of 6.1 cN/dtex to 7.5 cN/dtex. 
     
     
         9 . The polyamide multifilament according to  claim 7 , having a total fineness of 20 dtex to 44 dtex. 
     
     
         10 . A knitted lace produced using the polyamide multifilament according to  claim 7  as a ground lace yarn. 
     
     
         11 . A method of producing the polyamide multifilament according to  claim 7 , the method comprising:
 ejecting a molten polyamide resin from a spinneret to form filaments;   cooling and solidifying each of the filaments; and   drawing the obtained filaments,   wherein the method is performed using a polyamide multifilament production device including at least:   a spinneret that ejects a molten polyamide resin to form filaments;   a heating cylinder to gradually cool the filaments;   a cooling device that cools and solidifies the filaments;   a fluid swirling nozzle device for imparting convergence to yarns by a swirling flow;   a take-up roller for taking-up and drawing the filaments; and   a drawing device for drawing the filaments, and   wherein conditions (A) to (D) are satisfied:   (A) the heating cylinder is provided above the cooling device;   (B) the fluid swirling nozzle device is provided above the take-up roller;   (C) the drawing device is a multi-stage drawing device having two or more stages; and   (D) a low relaxation heat treatment is performed immediately after multi-stage drawing.   
     
     
         12 . The method according to  claim 11 , wherein the relaxation heat treatment is performed between a drawing roller and a relaxing roller at a relaxing ratio of 0 to 1.5% and a heat set temperature of 150° C. to 200° C. 
     
     
         13 . The polyamide multifilament according to  claim 8 , having a total fineness of 20 dtex to 44 dtex. 
     
     
         14 . A knitted lace produced using the polyamide multifilament according to  claim 8  as a ground lace yarn. 
     
     
         15 . A knitted lace produced using the polyamide multifilament according to  claim 9  as a ground lace yarn. 
     
     
         16 . A knitted lace produced using the polyamide multifilament according to  claim 13  as a ground lace yarn. 
     
     
         17 . A method of producing the polyamide multifilament according to  claim 8 , the method comprising:
 ejecting a molten polyamide resin from a spinneret to form filaments;   cooling and solidifying each of the filaments; and   drawing the obtained filaments,   wherein the method is performed using a polyamide multifilament production device including at least:   a spinneret that ejects a molten polyamide resin to form filaments;   a heating cylinder that gradually cools the filaments;   a cooling device that cools and solidifies the filaments;   a fluid swirling nozzle device that imparts convergence to yarns by a swirling flow;   a take-up roller that takes-up and draws the filaments; and   a drawing device that draws the filaments, and   wherein conditions (A) to (D) are satisfied:   (A) the heating cylinder is provided above the cooling device;   (B) the fluid swirling nozzle device is provided above the take-up roller;   (C) the drawing device is a multi-stage drawing device having two or more stages; and   (D) a low relaxation heat treatment is performed immediately after multi-stage drawing.   
     
     
         18 . A method of producing the polyamide multifilament according to  claim 9 , the method comprising:
 ejecting a molten polyamide resin from a spinneret to form filaments;   cooling and solidifying each of the filaments; and   drawing the obtained filaments,   wherein the method is performed using a polyamide multifilament production device including at least:   a spinneret that ejects a molten polyamide resin to form filaments;   a heating cylinder to gradually cool the filaments;   a cooling device that cools and solidifies the filaments;   a fluid swirling nozzle device that imparts convergence to yarns by a swirling flow;   a take-up roller that takes-up and draws the filaments; and   a drawing device that draws the filaments, and   wherein conditions (A) to (D) are satisfied:   (A) the heating cylinder is provided above the cooling device;   (B) the fluid swirling nozzle device is provided above the take-up roller;   (C) the drawing device is a multi-stage drawing device having two or more stages; and   (D) a low relaxation heat treatment is performed immediately after multi-stage drawing.   
     
     
         19 . A method of producing the polyamide multifilament according to  claim 13 , the method comprising:
 ejecting a molten polyamide resin from a spinneret to form filaments;   cooling and solidifying each of the filaments; and   drawing the obtained filaments,   wherein the method is performed using a polyamide multifilament production device including at least:   a spinneret that ejects a molten polyamide resin to form filaments;   a heating cylinder that gradually cools the filaments;   a cooling device that cools and solidifies the filaments;   a fluid swirling nozzle device that imparts convergence to yarns by a swirling flow;   a take-up roller that takes-up and draws the filaments; and   a drawing device that draws the filaments, and   wherein conditions (A) to (D) are satisfied:   (A) the heating cylinder is provided above the cooling device;   (B) the fluid swirling nozzle device is provided above the take-up roller;   (C) the drawing device is a multi-stage drawing device having two or more stages; and   (D) a low relaxation heat treatment is performed immediately after multi-stage drawing.   
     
     
         20 . The method according to  claim 17 , wherein the relaxation heat treatment is performed between a drawing roller and a relaxing roller at a relaxing ratio of 0 to 1.5% and a heat set temperature of 150° C. to 200° C. 
     
     
         21 . The method according to  claim 18 , wherein the relaxation heat treatment is performed between a drawing roller and a relaxing roller at a relaxing ratio of 0 to 1.5% and a heat set temperature of 150° C. to 200° C. 
     
     
         22 . The method according to  claim 19 , wherein the relaxation heat treatment is performed between a drawing roller and a relaxing roller at a relaxing ratio of 0 to 1.5% and a heat set temperature of 150° C. to 200° C.