Process for Forming a Cold-Stretched Drawstring Trash Bag

Abstract

The present invention is directed to a drawstring bag comprised from a first panel and a second panel. The first panel and the second panel are joined along a first side, a bottom, and a second side. The first panel and the second panel thereby define an upper opening of the bag. The drawstring bag may further comprise a first hem located along the upper opening of the bag in the first panel and a first drawstring may be disposed within the first hem. The first drawstring may be manufactured from a drawtape film subjected to a cold-stretch process.

What is claimed is: 
     
         1 . A cold-stretch process for forming a cold-stretched drawtape film for a drawstring of a drawstring bag comprising:
 maintaining the drawtape film at a temperature below a Vicat softening point of the drawtape film,   stretching the drawtape film wherein strain is induced in the drawtape film, and   relaxing the drawtape film wherein a portion of strain induced into the drawtape film is released.   
     
     
         2 . The cold-stretch process of  claim 1  further comprising:
 heating the drawtape film to a temperature below the Vicat softening point of the drawtape film. 
 
     
     
         3 . The cold-stretch process of  claim 1  wherein:
 the drawtape film is stretched by one or more cold-stretch rollers operating at a cold-stretch speed after being fed through one or more input rollers operating at an input speed, and 
 the drawtape film is relaxed by one or more relaxation rollers operating at a relaxation speed. 
 
     
     
         4 . The cold-stretch process of  claim 3  further comprising:
 the cold-stretch speed greater than the input speed, and 
 the relaxation speed less than the cold-stretch speed and greater than the input speed. 
 
     
     
         5 . The cold-stretch process of  claim 4  further comprising:
 the cold-stretch speed between 150% and 250% of the input speed, and 
 the relaxation speed between 50% and 90% of the cold-stretch speed. 
 
     
     
         6 . The cold-stretch process of  claim 5  wherein the input speed is approximately 200 feet per minute. 
     
     
         7 . The cold-stretch process of  claim 6  wherein the cold-stretch speed is approximately 400 feet per minute. 
     
     
         8 . The cold-stretch process of  claim 7  wherein the relaxation speed is approximately 300 feet per minute. 
     
     
         9 . The cold-stretch process of  claim 1  further comprising:
 one or more cold-stretch rollers stretching the drawtape film to a strain point adjacent to the deformation limit of the drawtape film. 
 
     
     
         10 . The cold-stretch process of  claim 1  further comprising:
 one or more cold-stretch rollers stretching the drawtape film to a strain point past the deformation limit of the drawtape film. 
 
     
     
         11 . The cold-stretch process of  claim 1  wherein:
 the drawtape film is stretched approximately 80 percent of an un-stretched length to a stretched length, and 
 the drawtape film is relaxed approximately 20 percent of the stretched length. 
 
     
     
         12 . The cold-stretch process of  claim 5  wherein:
 the input speed is approximately 325 feet per minute, 
 the cold-stretch speed is approximately 580 feet per minute, and 
 the relaxation speed is approximately 465 feet per minute. 
 
     
     
         13 . The cold-stretch process of  claim 1  wherein the drawtape film is in a fully solid state when stretched. 
     
     
         14 . A cold-stretch process for forming a cold-stretched drawtape film for a drawstring of a drawstring bag comprising:
 stretching the drawtape film wherein strain is induced in the drawtape film, and   relaxing the drawtape film wherein a portion of strain induced into the drawtape film is released.   
     
     
         15 . The cold-stretch process of  claim 14  wherein the drawtape film is in a fully solid state when stretched. 
     
     
         16 . The cold-stretch process of  claim 14  further comprising:
 one or more cold-stretch rollers stretching the drawtape film to a strain point adjacent to the deformation limit of the drawtape film. 
 
     
     
         17 . The cold-stretch process of  claim 14  further comprising:
 one or more cold-stretch rollers stretching the drawtape film to a strain point past the deformation limit of the drawtape film. 
 
     
     
         18 . The cold-stretch process of  claim 14  further comprising:
 heating the drawtape film to a temperature below the Vicat softening point of the drawtape film. 
 
     
     
         19 . The cold-stretch process of  claim 14  wherein:
 the drawtape film is stretched by one or more cold-stretch rollers operating at a cold-stretch speed after being fed through one or more input rollers operating at an input speed, and 
 the drawtape film is relaxed by one or more relaxation rollers operating at a relaxation speed. 
 
     
     
         20 . The cold-stretch process of  claim 19  further comprising:
 the cold-stretch speed greater than the input speed, and 
 the relaxation speed less than the cold-stretch speed and greater than the input speed.