Electrostatic dissipating fabric and garments formed therefrom

Abstract

Electrostatic dissipating fabrics incorporating spun yarns which include conductive staple fiber constituents incorporated within the spun yarns. The fabrics may be of either a woven or knit construction. The conductive fiber constituents are dispersed at an effective concentration to establish a network of charge carrying junctions within and between the individual yarns. The large number of junctions between the yarns facilitates the dissipation of static electricity between regions of a garment formed by the yarns. In particular, the fabric retains a high degree of conductivity across seams within the garment even after multiple washings.

What is claimed is:  
     
         1 . A static electricity dissipating fabric comprising a plurality of spun yarns held together in crossing relation to one another in a coordinated woven or knit construction, wherein said spun yarns comprise a plurality of electrically conductive staple fibers in spun relation with a plurality of substantially nonconductive natural or synthetic staple fibers and wherein said plurality of electrically conductive staple fibers are dispersed throughout said spun yarns such that said plurality of electrically conductive staple fibers define a network of electrically conductive junctions along the length of said spun yarns and between said spun yarns at locations where said spun yarns meet.  
     
     
         2 . A static electricity dissipating fabric as recited in  claim 1 , wherein said spun yarns are ring spun yarns.  
     
     
         3 . A static electricity dissipating fabric as recited in  claim 1 , wherein said spun yarns are open end spun yarns.  
     
     
         4 . A static electricity dissipating fabric as recited in  claim 1 , wherein said spun yarns are air jet spun yarns.  
     
     
         5 . A static electricity dissipating fabric as recited in  claim 1 , wherein said substantially nonconductive natural or synthetic staple fibers are selected from the group consisting of polyester staple fiber fibers, cotton staple fibers and blends thereof.  
     
     
         6 . A static electricity dissipating fabric as recited in  claim 1 , wherein said plurality of spun yarns comprise about 65% to about 99% by weight polyester staple fibers and about 0% to about 34% by weight cotton fibers and about 1% to about 5% by weight of electrically conductive carbonaceous staple fibers of substantially linear geometry.  
     
     
         7 . A static electricity dissipating fabric as recited in  claim 6 , wherein said static electricity dissipating fabric is of a woven construction and wherein said static electricity dissipating fabric is characterized by an electrical resistance in the range of about to about 100,000 to about 100,000,000 ohms per square when measured according to AATCC Test Method 76-1987 using a 100 volt potential and 1 inch electrode spacing at 20% relative humidity.  
     
     
         8 . A static electricity dissipating fabric comprising a plurality of spun yarns held together in crossing woven relation to one another, wherein said spun yarns comprise a plurality of electrically conductive carbonaceous staple fibers of substantially linear geometry in spun relation with a plurality of substantially nonconductive natural or synthetic staple fibers and wherein said plurality of electrically conductive carbonaceous staple fibers are dispersed throughout said spun yarns such that said plurality of electrically conductive carbonaceous staple fibers define a network of electrically conductive junctions along the length of said spun yarns and between said spun yarns at locations where portions of said spun yarns meet within the fabric.  
     
     
         9 . A static electricity dissipating fabric as recited in  claim 8 , wherein said spun yarns are ring spun yarns.  
     
     
         10 . A static electricity dissipating fabric as recited in  claim 8 , wherein said spun yarns are open end spun yarns.  
     
     
         11 . A static electricity dissipating fabric as recited in  claim 8 , wherein said spun yarns are air jet spun yarns.  
     
     
         12 . A static electricity dissipating fabric as recited in  claim 8 , wherein said substantially nonconductive natural or synthetic staple fibers are selected from the group consisting of polyester staple fiber fibers, cotton staple fibers and blends thereof.  
     
     
         13 . A static electricity dissipating fabric as recited in  claim 8 , wherein said plurality of spun yarns comprise about 65% to about 99% by weight polyester staple fibers and about 0% to about 34% by weight cotton fibers and about 1% to about 5% by weight of electrically conductive carbonaceous staple fibers of substantially linear geometry.  
     
     
         14 . A static electricity dissipating fabric as recited in  claim 13 , wherein said static electricity dissipating fabric is characterized by an electrical resistance in the range of about to about 100,000 to about 100,000,000 ohms per square when measured according to AATCC Test Method 76-1987 using a 100 volt potential and 1 inch electrode spacing at 20% relative humidity.  
     
     
         15 . A static electricity dissipating fabric as recited in  claim 13 , wherein the electrically conductive carbonaceous staple fibers are carbon suffused acrylic fibers.  
     
     
         16 . A static electricity dissipating fabric as recited in  claim 15 , wherein the carbon suffused acrylic fibers are characterized by a staple length of about 0.5 to about 3.5 inches.  
     
     
         17 . A static electricity dissipating fabric of woven construction having a warp direction and a fill direction, said static electricity dissipating fabric comprising a plurality of spun yarns disposed in both the warp direction and the fill direction and wherein said spun yarns comprise a plurality of electrically conductive carbonaceous staple fibers of substantially linear geometry in spun relation with a plurality of substantially nonconductive natural or synthetic staple fibers and wherein said plurality of electrically conductive carbonaceous staple fibers are dispersed throughout said spun yarns such that said plurality of electrically conductive carbonaceous staple fibers define a network of electrically conductive junctions along the length of said spun yarns and between said spun yarns at locations where portions of said spun yarns meet within the fabric, wherein said plurality of spun yarns comprise about 65% to about 99% by weight polyester staple fibers and about 0% to about 34% by weight cotton fibers and about 1% to about 5% by weight of electrically conductive carbonaceous staple fibers of substantially linear geometry.  
     
     
         18 . A static electricity dissipating fabric as recited in  claim 17 , wherein said static electricity dissipating fabric is characterized by an electrical resistance in the range of about to about 100,000 to about 100,000,000 ohms per square when measured according to AATCC Test Method 76-1987 using a 100 volt potential and 1 inch electrode spacing at 20% relative humidity.  
     
     
         19 . A static electricity dissipating fabric as recited in  claim 17 , wherein said spun yarns are ring spun yarns.  
     
     
         20 . A static electricity dissipating fabric as recited in  claim 17 , wherein said spun yarns are open end spun yarns.  
     
     
         21 . A static electricity dissipating fabric as recited in  claim 17 , wherein said spun yarns are air jet spun yarns.  
     
     
         22 . A garment formed from seamed panels of the static electricity dissipating fabric as recited in  claim 17 .  
     
     
         23 . A garment as recited in  claim 22 , wherein said garment is a lab coat and wherein said lab coat is characterized by a sleeve to sleeve electrical resistance of less than about 100,000,000 ohms after 100 washings when measured according to ESD Association Test Method STM 2.1-1997 at 10 volts and 12% relative humidity.  
     
     
         24 . A garment as recited in  claim 22 , wherein said garment is a lab coat and wherein said lab coat is characterized by a sleeve to sleeve electrical resistance in the range of less than about 10,000,000 ohms after 100 washings when measured according to ESD Association Test Method STM 2.1-1997 at 10 volts and 12% relative humidity.  
     
     
         25 . A garment as recited in  claim 22 , wherein said garment is a lab coat and wherein said lab coat is characterized by a sleeve to sleeve electrical resistance of less than about 5,000,000 ohms after 100 washings when measured according to ESD Association Test Method STM 2.1-1997 at 10 volts and 12% relative humidity.