Slip-cling stretch film

Abstract

A multilayer stretch film having a high slip surface and an aggressive cling surface for wrapping items or loads for ease of transport is disclosed. In one embodiment, there is disclosed a multilayer film comprises a first surface having a coefficient of friction at least less than about 0.9, comprising at least polypropylene and high-density polyethylene, a second surface having a cling force to the first surface at least greater than about 5 g/in, comprising at least a styrenic block copolymer, and a core layer, positioned between the first surface and the second surface, comprising at least linear low-density polyethylene or its blend.

1 - 28 . (canceled) 
     
     
         29 . A multilayer film comprising
 a slip layer comprising at least a polypropylene copolymer and high-density polyethylene blend,   a cling layer comprising at least a styrenic block copolymer and a polyethylene resin, and   an intermediary layer comprising one layer or a plurality of individual layers,   wherein at least one layer of the intermediary layer comprises linear low-density polyethylene resin or its blend and   wherein the cling layer contains from about 50% to about 95% of the styrenic block copolymer by weight and from about 5% to about 50% of the polyethylene resin by weight.   
     
     
         30 . The multilayer film of  claim 29 , wherein at least one layer of the intermediary layer comprises titanium dioxide. 
     
     
         31 . The multilayer film of  claim 29 , wherein the film comprises the slip layer in about 5% to about 20% by weight of the film, the cling layer in about 3% to about 20% by weight of the film, and the intermediary layer in about 60% to about 90% by weight of the film. 
     
     
         32 . The multilayer film of  claim 31 , wherein the film comprises the slip layer in about 15% by weight of the film, the cling layer in about 7% by weight of the film, and the intermediary layer in about 78% by weight of the film. 
     
     
         33 . The multilayer film of  claim 29 , wherein the slip layer has a coefficient of friction between about 0.3 to about 0.9, and wherein the cling layer has a cling force to the slip layer between about 5 g/in to about 80 g/in. 
     
     
         34 . The multilayer film of  claim 33 , wherein the slip layer has a coefficient of friction of about 0.5, and wherein the cling layer has a cling force to the slip layer of about 50 g/in. 
     
     
         35 . The multilayer film of  claim 29 , wherein the slip layer comprises between about 70% and about 99% by weight polypropylene and between about 1% to about 30% by weight high-density polyethylene. 
     
     
         36 . The multilayer film of  claim 35 , wherein slip layer comprises about 80% by weight polypropylene and about 20% by weight high-density polyethylene. 
     
     
         37 . The multilayer film of  claim 29 , wherein the intermediary layer comprises between about 50% and 100% by weight linear low-density polyethylene. 
     
     
         38 . The multilayer film of  claim 37 , wherein the intermediary layer further comprises between about 0.1% to about 5% by weight titanium dioxide. 
     
     
         39 . The multilayer film of  claim 38 , wherein the intermediary layer comprises about 98% by weight linear low-density polyethylene and about 2% by weight titanium dioxide. 
     
     
         40 . The multilayer film of  claim 29 , wherein the multilayer film can withstand a forced stretch of the film to about 400% at about 5000 psi. 
     
     
         41 . The multilayer film of  claim 29 , wherein the overall multilayer film thickness is between about 0.012 mm to about 0.125 mm. 
     
     
         42 . The multilayer film of  claim 41 , wherein the overall multilayer film thickness is about 0.025 mm. 
     
     
         43 . The multilayer film of  claim 29 , wherein the at least one layer of the intermediary layer further comprises a material selected from the group consisting of metallocene-catalyzed low-density polyethylene, low-density polyethylene, mid-density polyethylene, high-density polyethylene, polypropylene, and any homopolymers, copolymers or blend thereof. 
     
     
         44 . The multilayer film of  claim 29 , wherein the intermediary layer further comprises at least an additive. 
     
     
         45 . The multilayer film of  claim 29 , wherein the cling layer further comprises at least an additive. 
     
     
         46 . The multilayer film of  claim 29 , wherein the cling layer further comprises an ethylene-octene copolymer. 
     
     
         47 . A multilayer film comprising
 a first surface layer having a coefficient of friction at least less than about 0.9, comprising at least a polypropylene copolymer and high-density polyethylene,   a second surface layer having a cling force to the first surface layer at least greater than about 5 g/in, comprising at least a styrenic block copolymer and a polyethylene resin, and   a core layer, positioned between the first surface layer and the second surface layer, comprising one layer or a plurality layers,   wherein at least one layer of the core layer comprises linear low-density polyethylene resin or its blend and   wherein the second surface layer contains from about 50% to about 95% of the styrenic block copolymer by weight and from about 5% to about 50% of the polyethylene resin by weight.   
     
     
         48 . The multilayer film of  claim 47 , wherein the coefficient of friction of the first surface layer is about 0.5, and wherein the cling force of the second surface layer to the first surface layer is about 50 g/in. 
     
     
         49 . The multilayer film of  claim 47 , wherein the multilayer film comprises the first surface layer in between about 5% to about 20% by weight, the second surface layer in between about 3% to about 20% by weight, and the core layer in between about 60% to about 90% by weight. 
     
     
         50 . The multilayer film of  claim 47 , wherein the multilayer film comprises the first surface layer in about 15% by weight, the second surface layer in about 7% by weight, and the core layer in about 78% by weight. 
     
     
         51 . The multilayer film of  claim 47 , wherein the first surface layer comprises between about 75% and about 99% by weight polypropylene and between about 1% to about 25% by weight high-density polyethylene. 
     
     
         52 . The multilayer film of  claim 51 , wherein first surface layer comprises about 80% by weight polypropylene and about 20% by weight high-density polyethylene. 
     
     
         53 . The multilayer film of  claim 47 , wherein the second surface layer comprises between about 80% and 100% by weight of a styrenic block copolymer. 
     
     
         54 . The multilayer film of  claim 47 , wherein the core layer comprises between about 50% and 100% by weight linear low-density polyethylene. 
     
     
         55 . The multilayer film of  claim 54 , wherein the core layer further comprises between about 0.1% to about 5% by weight titanium dioxide. 
     
     
         56 . A multilayer film comprising
 a slip layer comprising at least a polypropylene copolymer and high-density polyethylene blend,   a cling layer comprising at least a styrenic block copolymer and an ethylene-octene copolymer resin, and   an intermediary layer comprising one layer or a plurality of individual layers,   wherein at least one layer of the intermediary layer comprises linear low-density polyethylene resin or its blend and   wherein the cling layer contains from about 50% to about 95% of the styrenic block copolymer by weight and from about 5% to about 50% of the ethylene-octene copolymer resin by weight.   
     
     
         57 . The multilayer film of  claim 56 , wherein the ethylene-octene copolymer resin has a density between about 0.850 g/cm 3  and about 0.900 g/cm 3 , as determined by ASTM test method D792. 
     
     
         58 . The multilayer film of  claim 56 , wherein the ethylene-octene copolymer resin has a MFR of about 3.0 g/10 min, as determined by ASTM test method D1238. 
     
     
         59 . The multilayer film of  claim 56 , wherein the ethylene-octene copolymer resin has a density of about 0.875 g/cm 3 , as determined by ASTM test method D792, and a MFR of about 3.0 g/10 min, as determined by ASTM test method D1238. 
     
     
         60 . The multilayer film of  claim 56 , wherein the cling layer further comprises low-density polyethylene resin. 
     
     
         61 . The multilayer film of  claim 60 , wherein the low-density polyethylene resin has a density between about 0.91 g/cm 3  and about 0.94 g/cm 3 , as determined by ASTM test method D792. 
     
     
         62 . The multilayer film of  claim 56 , wherein the cling layer further comprises LLDPE. 
     
     
         63 . The multilayer film of  claim 62 , wherein the LLDPE resin has a density between about 0.915 g/cm 3  and about 0.925 g/cm 3 , as determined by ASTM test method D792. 
     
     
         64 . The multilayer film of  claim 56 , wherein the cling layer further comprises VLDPE. 
     
     
         65 . The multilayer film of  claim 64 , wherein the VLDPE resin has a density between about 0.88 g/cm 3  and about 0.915 g/cm 3 , as determined by ASTM test method D792.