Polymeric sheets and articles wrapped therewith

Abstract

A polymeric sheet having low density and comprising a low to non-existent amount of cyclic olefinic polymers (COP) and/or cyclic olefinic copolymers (COC). The overall density of the sheet may be lower than water. The sheet may be stretched and then heat shrinked onto an article. The sheet may be used as a label or package to wrap articles therewith.

1 . A method for labeling an article with a polymeric sheet comprising:
 wrapping the polymeric sheet around the circumference of the article to obtain a labeled article; and   heating the labeled article to 100° C. or less, to allow the polymeric sheet to shrink by at least 20% of its original dimension along a machine direction thereof, to thereby follow the contours of the article,   the polymeric sheet having a density less than 1 g/cm.   
     
     
         2 . The method of  claim 1 , wherein the article comprises at least two portions with cross-sectional diameters that differ from one another by more than 20%, being circumferentially enveloped by the polymeric sheet. 
     
     
         3 . The method of  claim 1 , wherein the heating is carried out by steam. 
     
     
         4 . The method of  claim 1 , wherein the polymeric sheet is prepared by short-gap stretching. 
     
     
         5 . The method of  claim 1 , wherein the polymeric sheet comprises at least two materials, wherein at least one of the at least two materials has a density greater than 1 g/cm. 
     
     
         6 . The method of  claim 5 , wherein the polymeric sheet comprises up to 50 wt. % of cyclic olefinic copolymer and/or cyclic olefinic polymer (COC/COP). 
     
     
         7 . The method of  claim 6 , wherein the polymeric sheet comprises at least one material is polystyrene (PS) or PETg (Poly (ethylene terephthalate) glycol). 
     
     
         8 . The method of  claim 1 , wherein the polymeric sheet has a thickness of up to 50 μm. 
     
     
         9 . The method of  claim 1 , wherein the polymeric sheet is shrinkable along an axis perpendicular to the machine direction by no more than 5%. 
     
     
         10 . The method of  claim 1 , wherein the polymeric sheet is transparent. 
     
     
         11 . The method of  claim 1 , wherein the polymeric sheet has a density less than 1 g/cm 3  after shrinking. 
     
     
         12 . A method for labeling an article having at least two portions with cross-sectional diameters that differ from one another by more than 20%, the method comprising:
 (a) preparing a polymeric sheet, the polymeric sheet:
 being monoaxially stretched along the machine direction, 
 being heat shrinkable along the machine direction by at least 20% of its original dimension, 
 being transparent after shrinking, and having, prior to and after shrinking, a density of less than 1 g/cm 3 ; 
   (b) wrapping the polymeric sheet onto an outer surface of the article to obtain a labeled article; and   (c) monoaxially heat shrinking the labeled article at a temperature of about 100° C. to circumferentially envelop the at least two portions of the outer surface to closely and substantially uniformly follow the portions' contour.   
     
     
         13 . The method of  claim 12 , wherein the heat shrinking is carried out by steam. 
     
     
         14 . The method of  claim 12 , wherein the polymeric sheet is prepared by short-gap stretching. 
     
     
         15 . The method of  claim 12 , wherein the polymeric sheet comprises at least two materials, wherein at least one of the at least two materials has a density greater than 1 g/cm 3 . 
     
     
         16 . The method of  claim 15 , wherein the polymeric sheet comprises up to 50 wt. % of cyclic olefinic copolymer and/or cyclic olefinic polymer (COC/COP). 
     
     
         17 . The method of  claim 15 , wherein the at least one material is polystyrene (PS) or PETg (Poly(ethylene terephthalate) glycol). 
     
     
         18 . The method of  claim 15 , wherein the materials are in the form of layers.