Heat Sealable Packaging Material with Improved Hot Tack

Abstract

A packaging material includes a substrate and a heat seal layer. The heat seal layer comprises polyvinylidene chloride. The packaging material includes at least about 8 wt % moisture for increasing the hot tack of a seal formed between a first portion of the heat seal layer and a second portion of the heat seal layer relative to a packaging material with less than about 8 wt % moisture. If desired, the packaging material including the at least about 8 wt % moisture may be formed into a roll.

1 . A packaging material, comprising:
 a substrate, the substrate comprising paper; and   a heat seal layer disposed on the substrate, the heat seal layer comprising polyvinylidene chloride, wherein the packaging material includes at least about 8 wt % moisture.   
     
     
         2 . The packaging material of  claim 1 , wherein the packaging material includes from about 10 wt % to about 18 wt % moisture. 
     
     
         3 . The packaging material of  claim 1 , wherein the packaging material includes from about 12 wt % to about 16 wt % moisture. 
     
     
         4 . The packaging material of  claim 1 , wherein the packaging material includes about 14 wt % moisture. 
     
     
         5 . The packaging material of  claim 1 , wherein the moisture is substantially contained within the substrate. 
     
     
         6 . The packaging material of  claim 1 , wherein the packaging material is wound into a roll. 
     
     
         7 . The packaging material of  claim 1 , wherein the moisture is for increasing the hot tack of a seal formed between a first portion of the heat seal layer and a second portion of the heat seal layer relative to a seal formed using a packaging material with less than about 8 wt % moisture. 
     
     
         8 . The packaging material of  claim 7 , wherein the hot tack of the packaging material is at least about 25% greater than the hot tack of the packaging material with less than about 8 wt % moisture. 
     
     
         9 . The packaging material of  claim 7 , wherein the hot tack of the packaging material is at least about 40% greater than the hot tack of the packaging material with less than about 8 wt % moisture. 
     
     
         10 . The packaging material of  claim 7 , wherein the hot tack of the packaging material is at least about 75% greater than the hot tack of the packaging material with less than about 8 wt % moisture. 
     
     
         11 . The packaging material of  claim 7 , wherein the hot tack of the packaging material is at least about 100% greater than the hot tack of the packaging material with less than about 8 wt % moisture. 
     
     
         12 . The packaging material of  claim 1 , further comprising a polymer layer disposed between the substrate and the heat seal layer. 
     
     
         13 . The packaging material of  claim 12 , wherein the polymer layer comprises at least one of polyvinylidene chloride, ethylene vinyl alcohol, and barrier fluoropolymer. 
     
     
         14 . The packaging material of  claim 1 , further comprising a slip modifier disposed on a side of the substrate opposite the heat seal layer. 
     
     
         15 . The packaging material of  claim 1 , wherein the heat seal layer further comprises an anti-blocking material. 
     
     
         16 . The packaging material of  claim 1 , wherein the substrate further comprises a grease resistant material. 
     
     
         17 . The packaging material of  claim 16 , wherein the grease resistant material comprises a fluorochemical. 
     
     
         18 . The packaging material of  claim 1 , wherein the packaging material is repulpable. 
     
     
         19 . A packaging material, comprising:
 a substrate, the substrate comprising paper;   a first polymer layer disposed on the substrate, the first polymer layer comprising polyvinylidene chloride; and   a second polymer layer disposed on the first polymer layer, the second polymer layer comprising polyvinylidene chloride, the second polymer layer comprising an outermost surface of the packaging material,   wherein the packaging material includes at least about 8 wt % moisture.   
     
     
         20 . The packaging material of  claim 19 , wherein the hot tack of a seal formed between a first portion of the heat seal layer and a second portion of the heat seal layer is at least about 25% greater than the hot tack of a heat seal formed using a packaging material with less than about 8 wt % moisture. 
     
     
         21 . A method of forming a package, the method comprising:
 forming a packaging material into a tubular structure, the packaging material comprising
 a substrate, the substrate comprising paper, and 
 a heat seal layer disposed on the substrate, the heat seal layer comprising polyvinylidene chloride, the packaging material including at least about 8 wt % moisture, 
 wherein the tubular structure has a pair of opposed inner surfaces, each surface comprising the heat seal layer of the packaging material; and 
   bringing the inner surfaces into contact with one another in the presence of heat to form a seal.   
     
     
         22 . The method of  claim 21 , wherein the hot tack of the seal is at least about 25% greater than a packaging material with less than about 8 wt % moisture.