Sealant film, multilayer film including same and packaging bag

Abstract

A sealant film including a polyolefin layer containing polyolefin as a main ingredient, and a polycycloolefin layer as an outermost layer containing polycycloolefin as a main ingredient. The polycycloolefin contains two or more kinds of structural units selected from a structural unit (A) derived from a dicyclopentadiene compound, a structural unit (B) derived from a tetracyclododecene compound, and a structural unit (C) derived from a norbornene compound, and the polycycloolefin has a glass transition temperature less than or equal to 80° C.

What is claimed is: 
     
         1 . A sealant film comprising:
 a polyolefin layer containing polyolefin as a main ingredient; and   a polycycloolefin layer as an outermost layer containing polycycloolefin as a main ingredient,   wherein the polycycloolefin contains two or more kinds of structural units selected from a structural unit (A) derived from a dicyclopentadiene compound, a structural unit (B) derived from a tetracyclododecene compound, and a structural unit (C) derived from a norbornene compound, and   the polycycloolefin has a glass transition temperature less than or equal to 80° C.   
     
     
         2 . The sealant film according to  claim 1 , wherein the polycycloolefin contains the structural unit (A) derived from a dicyclopentadiene compound, the structural unit (B) derived from a tetracyclododecene compound and the structural unit (C) derived from a norbornene compound. 
     
     
         3 . The sealant film according to  claim 1 , wherein the polycycloolefin has a glass transition temperature greater than or equal to 40° C. 
     
     
         4 . The sealant film according to  claim 1 , wherein the dicyclopentadiene compound is tricyclo [5.2.1.0 2,6 ] deca-3,8-diene or a derivative of tricyclo [5.2.1.0 2,6 ] deca-3,8-diene, the tetracyclododecene compound is tetracyclo [4.4.0.1 2,5 .1 7,10 ]-3-dodecene or a derivative of tetracyclo [4.4.0.1 2,5 .1 7,10 ]-3-dodecene, and the norbornene compound is bicyclo [2.2.1] hept-2-ene or a derivative of bicyclo [2.2.1] hept-2-ene. 
     
     
         5 . The sealant film according to  claim 1 , wherein the polycycloolefin is a ring-opening metathesis polymer of two or more kinds of compounds selected from the dicyclopentadiene compound, the tetracyclododecene compound and the norbornene compound, and carbon-carbon double bonds are hydrogenated. 
     
     
         6 . A multilayer film comprising:
 a base sheet; and   the sealant film according to  claim 1 ,   the sealant film being stacked on the base sheet.   
     
     
         7 . The multilayer film according to  claim 6 , further comprising a gas barrier film stacked between the base sheet and the sealant film. 
     
     
         8 . The multilayer film according to  claim 6  having a thickness less than or equal to 100 μm. 
     
     
         9 . A packaging bag comprising the multilayer film according to  claim 6  sealed such that the sealant films are fused to each other. 
     
     
         10 . A sealant film comprising:
 a polyolefin layer containing polyolefin; and   a polycycloolefin layer as an outermost layer containing polycycloolefin as a main ingredient,   wherein the polycycloolefin contains two or more kinds of structural units selected from a structural unit (A) derived from a dicyclopentadiene compound, a structural unit (B) derived from a tetracyclododecene compound, and a structural unit (C) derived from a norbornene compound,   the polycycloolefin has a glass transition temperature less than or equal to 80° C.,   the polyolefin layer has a thickness greater than or equal to 10 μm and less than or equal to 40 m, and   the polycycloolefin layer has a thickness greater than or equal to 5 m and less than or equal to 20 μm.   
     
     
         11 . The sealant film according to  claim 10 , wherein the polyolefin layer contains less than or equal to 50% by mass polycycloolefin relative to a mass of the sealant film. 
     
     
         12 . A sealant film comprising:
 a polyolefin layer containing polyolefin; and   a polycycloolefin layer as an outermost layer containing polycycloolefin as a main ingredient,   wherein the polycycloolefin contains two or more kinds of structural units selected from a structural unit (A) derived from a dicyclopentadiene compound, a structural unit (B) derived from a tetracyclododecene compound, and a structural unit (C) derived from a norbornene compound,   the polycycloolefin has a glass transition temperature less than or equal to 80° C.,   the polycycloolefin layer has a thickness (T2) greater than or equal to 5 μm and less than or equal to 10 μm, and   a ratio (a) of a thickness (T1) of the polyolefin layer to the thickness (T2) of the polycycloolefin layer is greater than or equal to 3 and less than or equal to 9.