Film and packaging body

Abstract

An object of the present invention is to provide a film that is resistant to the effects of the surface condition of an adherend such as a carrier tape and demonstrates only small fluctuations in peel strength. The film according to the present invention is provided with a surface layer. The surface layer is formed by using a polymer blend as the main component thereof. The polymer blend comprises at least two types of single segment polymers, at least two types of multi-segment polymers, or at least one type of single segment polymer and at least one type of multi-segment polymer. In the film according to the present invention, the maximum value of the absolute value of the difference in solubility parameter values among all segments in the polymer blend is 0.40 to 1.40.

1 . A film provided with a surface layer having as a main component thereof a polymer blend comprising at least two types of single segment polymers, at least two types of multi-segment polymers, or at least one type of single segment polymer and at least one type of multi-segment polymer,
 wherein a maximum value of an absolute value of a difference in solubility parameter values among all segments in the polymer blend is 0.40 to 1.40.   
     
     
         2 . The film according to  claim 1 , wherein two specific segments having solubility parameter values serving as a basis for calculating the maximum value are contained at 15 parts by weight to 60 parts by weight based on 100 parts by weight of the polymer blend, and a weight ratio of one specific segment to the other specific segment is within a range of 30:70 to 70:30. 
     
     
         3 . The film according to  claim 1 , wherein at least one type of the segments has thermal adhesiveness, and the surface layer functions as a thermal adhesive layer. 
     
     
         4 . A packaging body provided with the film according to  claim 3  and a packaging container, an opening of which is covered by the film,
 wherein the absolute value of the difference between the solubility parameter value of the segment having thermal adhesiveness and the solubility parameter value of the main component of a resin composition that forms a surface around the opening of the packaging container is 1.90 or less. 
 
     
     
         5 . The packaging body according to  claim 4 , wherein peel strength of the film with respect to the packaging container (as measured in compliance with standards when using a carrier tape having a width of 8 mm as described in JIS C-0806-3) is 0.1 N to 1.0 N. 
     
     
         6 . The film according to  claim 2 , wherein at least one type of the segments has thermal adhesiveness, and the surface layer functions as a thermal adhesive layer. 
     
     
         7 . A packaging body provided with the film according to  claim 6  and a packaging container, an opening of which is covered by the film,
 wherein the absolute value of the difference between the solubility parameter value of the segment having thermal adhesiveness and the solubility parameter value of the main component of a resin composition that forms a surface around the opening of the packaging container is 1.90 or less. 
 
     
     
         8 . The packaging body according to  claim 7 , wherein peel strength of the film with respect to the packaging container (as measured in compliance with standards when using a carrier tape having a width of 8 mm as described in JIS C-0806-3) is 0.1 N to 1.0 N.