Thermoplastic resin film and label paper employing the same

Abstract

A thermoplastic resin film (i) which has a degree of dimensional change through heating and cooling (α) in the range of from −2% to 2% as measured by thermomechanical analysis in the range of from room temperature to 135° C., or which has a degree of thermal shrinkage of 1.8% or lower upon heating at 130° C. for 30 minutes or longer; and a label paper employing the same. The label paper has suitability for heated-roll fixing type electrophotographic printers and is satisfactory in curling after printing.

1 . A thermoplastic resin film (i) comprising a stretched thermoplastic resin sheet comprising a thermoplastic resin, wherein the thermoplastic resin film has a degree of dimensional change after heating and cooling (α) in the range of from −2% to 2% as measured by thermomechanical analysis in the range of from room temperature to 135° C. or which has a degree of thermal shrinkage of 1.8% or lower upon heating at 130° C. for 30 minutes or longer.  
     
     
         2 . The thermoplastic resin film (i) according to    claim 1   , having a degree of dimensional change after heating and cooling (α) in the range of from −2% to 2% as measured by thermomechanical analysis in the range of from room temperature to 135° C.  
     
     
         3 . The thermoplastic resin film (i) according to    claim 1   , having a degree of thermal shrinkage of 1.8% or lower upon heating at 130° C. for 30 minutes or longer.  
     
     
         4 . The thermoplastic resin film (i) according to    claim 1   , having a degree of dimensional change after heating and cooling (α) in the range of from −2% to 2% as measured by thermomechanical analysis in the range of from room temperature to 135° C., and having a degree of thermal shrinkage of 1.8% or lower upon heating at 130° C. for 30 minutes or longer.  
     
     
         5 . The thermoplastic resin film (i) according to any one of    claims 1    to    4   , comprising from 35 to 100 wt % of a thermoplastic resin and from 65 to 0 wt % of inorganic and/or organic fine particles.  
     
     
         6 . The thermoplastic resin film (i) according to any one of    claims 1    to    5   , wherein the thermoplastic resin is a porosity as shown by the following equation of from 8 to 60%:  
         Porosity                   (   %   )       =           ρ   0     -   ρ       ρ   0       ×   100                   

 ρ 0 : density of the resin film before stretching  
 ρ: density of the resin film after stretching.  
 
     
     
         7 . The thermoplastic resin film (i) according to any one of    claims 1    to    6   , wherein the thermoplastic polyolefin resin is a polyolefin-based resin.  
     
     
         8 . The thermoplastic resin film (i) according to    claim 7   , wherein the polyolefin-based resin is a polypropylene-based resin.  
     
     
         9 . The thermoplastic resin film (i) according to any one of    claims 6    to    8   , which has an opacity as measured in accordance with JIS-P8138-1976 of from 20% to 100%.  
     
     
         10 . The thermoplastic resin film (i) according to any one of    claims 1    to    9   , which is one obtained through a heat treatment.  
     
     
         11 . The thermoplastic resin film (i) according to    claim 10   , wherein the heat treatment is carried out at 90° C. to 250° C.  
     
     
         12 . The thermoplastic resin film (i) according to    claim 10    or    11   , wherein the heat treatment is carried out in an oven.  
     
     
         13 . The thermoplastic resin film according to any one of    claims 1    to    12   , which comprises a toner receiving layer on one side thereof.  
     
     
         14 . The thermoplastic resin film according to any one of    claims 1    to    13   , which comprises a toner receiving layer on at least the side thereof opposite to the side in contact with a pressure-sensitive adhesive layer.  
     
     
         15 . A label paper which comprises a thermoplastic resin film (i), a pressure-sensitive adhesive layer (ii), and a release payer (iii), in this order on the thermoplastic resin film (i), wherein the thermoplastic resin film (i) is the thermoplastic resin film (i) according to any one of    claims 1    to    14   .  
     
     
         16 . The label paper according to    claim 15   , wherein a A-4 size (210 mm×297 mm) paper has an average curl height at the four corners of 50 mm or smaller, measured 2 minutes after printing the label paper with a heated-roll fixing type electrophotographic printer.  
     
     
         17 . The label paper according to    claim 15    or    16   , wherein the thermoplastic resin film (i) has a degree of dimensional change after heating and cooling (α) in the range of from −2% to 2% as measured by thermomechanical analysis in the range of from room temperature to 135° C., and the difference (α-β) between the degree of dimensional change (α) of the film and the degree of dimensional change after heating and cooling (β) of the release paper (iii), as measured by thermomechanical analysis in the range of from room temperature to 135° C., is in the range of from −1.5% to 1.5%.