Yarn filament and method for making same

Abstract

This invention relates to a trilobal filament having at least one axially extending void, preferably one elongated void in each lobe, wherein each lobe has a partial elliptical-shaped profile having a major axis to minor axis of between about 1.04:1 to about 1.12:1, the cross-section has a modification ratio of 1.7 to 2.2, and the total cross-sectional area is 7 to 13 percent void. In a further aspect, this invention is a spinnerette for producing a filament comprising at least one bore group. Each bore group having three leg sections that are divergent from each other by 100° to 130° and each leg section includes two substantially parallel long leg capillary sections extending to an end section having a shoulder that extends inwardly toward a central axis of the long leg capillary sections.

What is claimed is: 
     
         1 . A filament comprising a trilobal cross-section and at least one elongated void, wherein each lobe has a partial elliptical-shaped profile having a major axis to minor axis of between about 1.04:1 to about 1.12:1, wherein each elongated void has an elliptical-shape having a major axis that is oriented at an angle β with respect to the major axis of the respective lobe, wherein the cross-section has a modification ratio of 1.7 to 2.2, and wherein the total cross-sectional area is between about 5 to 15 percent void. 
     
     
         2 . The filament of  claim 1 , wherein there are three elongated voids. 
     
     
         3 . The filament of  claim 2 , wherein there is one elongated void in each lobe. 
     
     
         4 . The filament of  claim 1 , wherein each lobe has a pair of spaced foci, wherein each void has a pair of spaced foci, and wherein one foci of the lobe and one foci of the void are positioned in substantially the same cross-sectional position. 
     
     
         5 . The filament of  claim 3 , wherein the angle β ranges from between about 0 degrees (substantially co-axial) to about 60 degrees. 
     
     
         6 . The filament of  claim 3 , wherein the angle β ranges from between about 0 degrees to about 45 degrees. 
     
     
         7 . The filament of  claim 3 , wherein at least one or more voids are oriented at a different β. 
     
     
         8 . The filament of  claim 7 , wherein the angle β for all of the elongated voids differ. 
     
     
         9 . The filament of  claim 1 , wherein the cross-section of the filament has a modification ratio of at least 2.0. 
     
     
         10 . The filament of  claim 1 , wherein the filament comprises a synthetic material selected from the group consisting of polyamide, polyester, polyolefin and acrylic. 
     
     
         11 . The filament of  claim 10 , wherein the synthetic material is selected from the group consisting of nylon 6 and nylon 66. 
     
     
         12 . The filament of  claim 10 , wherein the synthetic material is selected from the group consisting of polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), and polybutylene terephthalate (PBT). 
     
     
         13 . A yarn comprising at least one filament comprising a trilobal cross-section and at least one elongate void, wherein each lobe has a elliptical-shaped profile having a major axis to minor axis of between about 1.04:1 to about 1.12:1, wherein each elongated void has an elliptical-shape having a major axis that is oriented at an angle β with respect to the major axis of the respective lobe, wherein the cross-section has a modification ratio of 1.7 to 2.2, and wherein the total cross-sectional area is between about 5 to 15 percent void. 
     
     
         14 . The yarn of  claim 13 , wherein there are three elongate voids. 
     
     
         15 . The yarn of  claim 14 , wherein there is one elongate void in each lobe. 
     
     
         16 . The yarn of  claim 15 , wherein each lobe has a pair of spaced foci, wherein each void has a pair of spaced foci, and wherein one foci of the lobe and one foci of the void are positioned in substantially the same in cross-section. 
     
     
         17 . The yarn of  claim 15 , wherein the angle β ranges from between about 0 degrees (substantially co-axial) to about 60 degrees. 
     
     
         18 . The yarn of  claim 15 , wherein the angle β ranges from between about 0 degrees to about 45 degrees. 
     
     
         19 . The yarn of  claim 15 , wherein at least one or more voids are oriented at a different β. 
     
     
         20 . The yarn of  claim 18 , wherein the angle β for all of the elongated voids differ.