Soft hand, low luster, high body carpet filaments

Abstract

Novel filaments and yarns for carpets, upholstery and other applications, the spinneret and method for their production and carpets manufactured therefrom. The filaments of the invention are solid multi-lobal filaments of complex convex-concave surface contour possessing low luster, low moment of inertia, high color intensity upon dyeing and high covering power. Carpets manufactured therefrom possess low luster, soft hand, high covering power and high body suitable for premium residential application. The filaments of the invention are produced at high throughput and productivity by the method of the invention.

What is claimed is:  
     
         1 . A filament comprising a solid cross-section having a perimeter comprised of a plurality of lobes that are joined to one another by concave line segments, said cross-section having a modification ratio of about 2.4 to about 5; wherein upon traversing in one direction completely around the perimeter, the position of a center of curvature for the perimeter changes from one side of said perimeter to the other side at least eighteen times.  
     
     
         2 . The filament of  claim 1 , wherein each lobe of the filament is comprised of a convex region; a concave transition region; and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic or straight.  
     
     
         3 . The filament of  claim 1 , wherein each lobe of the filament is comprised of a first convex region; a first concave transition region; a second convex region; a second concave transition region; and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic or straight.  
     
     
         4 . The filament of  claim 1 , wherein each lobe of said filament has a composite curve profile having a first arm angle α of about 50 to about 30°; and a second arm angle β of about 60° to about 85°; and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic and straight.  
     
     
         5 . The filament of  claim 1 , wherein each lobe of said filament has a composite curve profile having a first arm angle α of about 5° to about 30°; a second arm angle β of about 60° to about 85°; and a third arm angle γ of about 60° to about 85°; and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic and straight.  
     
     
         6 . The filament of  claim 1 , wherein the number of lobes is at least three.  
     
     
         7 . The filament of  claim 6 , wherein the lobes are substantially equispaced.  
     
     
         8 . The filament of  claim 1 , wherein the number of lobes is three, four or five.  
     
     
         9 . The filament of either  claim 2 ,  3 ,  4  or  5 , wherein said lateral walls of said nipple section are essentially straight and parallel.  
     
     
         10 . The filament of either  claim 2 ,  3 ,  4  or  5 , wherein said lateral walls of said nipple section are essentially straight and converging.  
     
     
         11 . The filament of either  claim 2 ,  3 ,  4  or  5 , wherein said nipple section has a perimeter selected from the group consisting of parabolic or elliptical.  
     
     
         12 . A yarn comprised of a plurality of the filaments of  claim 1 .  
     
     
         13 . The yarn of  claim 12 , further comprising about 0.05 to about 3 wt. % of heat activated binder fibers.  
     
     
         14 . The yarn of  claim 12 , wherein said multi-lobal filaments are selected from the group consisting of trilobal filaments, tetralobal filaments, pentalobal filaments, and mixtures thereof.  
     
     
         15 . The yarn of  claim 12  wherein said multi-lobal filaments are trilobal filaments.  
     
     
         16 . The yarn of  claim 12  wherein each lobe comprises a convex region; a concave transition region; and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic or straight.  
     
     
         17 . The yarn of  claim 12  wherein each lobe comprises a first convex region; a first concave transition region; a second convex region; a second concave transition region; and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic or straight.  
     
     
         18 . The yarn of  claim 12  wherein each lobe has a composite curve profile comprising a convex region defining an arm angle β ranging from 60° to 85°, a concave transition region, and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic or straight.  
     
     
         19 . The yarn of  claim 12  wherein each lobe has a composite curve profile comprising a first arm angle α of about 5° to about 30°; a second arm angle β of about 60° to about 85°; a third arm angle γ of about 60° to about 85°; and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic and straight.  
     
     
         20 . The yarn of any one of claims  16 ,  17 ,  18  and  19  wherein said lateral walls of said nipple section are essentially straight and parallel.  
     
     
         21 . The yarn of any one of claims  16 ,  17 ,  18  and  19  wherein said lateral walls of said nipple section are essentially straight and converging.  
     
     
         22 . The yarn of any one of claims  16 ,  17 ,  18  and  19  wherein said nipple section has a perimeter selected from the group consisting of parabolic or elliptical.  
     
     
         23 . A carpet comprised of multi-filament yarns of  claim 12 .  
     
     
         24 . The carpet of  claim 23  wherein each lobe has a first an arm angle α ranging from about 5° to about 30°, a second arm angle β ranging from about 60° to about 85°, and a nipple section extending to the outermost point of the lobe, said nipple section having lateral walls selected from the group consisting of elliptical, parabolic and straight.  
     
     
         25 . The carpet of  claim 23  wherein said lateral walls of said nipple section are straight and converging.  
     
     
         26 . A capillary spinneret orifice comprising: at least three essentially identical legs originating at a central point in a multi-lobal central region; one or more contiguous bulge regions extending along each such leg from said multi-lobal central region, and a nipple section extending from the outermost said bulge region to the outermost point of each said leg.  
     
     
         27 . The capillary spinneret orifice of  claim 27  wherein the orifice area is about 4×10 −4  in 2  (0.26 mm 2 ) to about 11×10 −4  in 2  (0.71 mm 2 ) and the width of the nipple section is about 0.0030 inches (0.0762 mm) to about 0.004 inches (0.106) mm).  
     
     
         28 . A method of yarn production comprising the steps of: 
 (a) forming a melt of a filament-forming synthetic polymer;    (b) placing said melt in communication with a capillary spinneret, said spinneret defining a plurality of orifices, wherein each said orifice is comprised of multiple legs originating at a central point in a multi-lobal central region, one or more contiguous bulge regions extending along each such leg from said multi-lobal central region, and a nipple section extending from the outermost said bulge region to the outermost point of the leg;    (c) extruding said melt through said orifices of said spinneret to form a melt stream;    (d) drawing the melt stream;    (e) cooling to solidify said melt stream to form a multi-filament yarn;    (f) and drawing said yarn to a total draw ratio of about 1.5:1 to about 3.6:1.