Coating solution for gas barrier, gas barrier laminate, packaging material and packaging material for heat sterilization

Abstract

This coating solution for a gas barrier contains an ammonium salt (A) of a polymer having a carboxyl group, a particulate multivalent metallic compound (B), and water, the content of the multivalent metallic compound (B) being about 0.5-2.0 times the chemical equivalent of the ammonium salt (A), and the mean particle diameter of the multivalent metallic compound (B) being about 4 μm or less.

What is claimed is: 
     
         1 . A coating solution for gas barrier, containing an ammonium salt (A) of a polymer including a carboxyl group, a particulate multivalent metallic compound (B) and water, wherein:
 the multivalent metallic compound (B) content is about 0.5 to 2.0 times the chemical equivalent of the ammonium salt (A); and   mean particle size of the multivalent metallic compound (B) is about or less.   
     
     
         2 . The coating solution for gas barrier according to clam 1, wherein the multivalent metallic compound (B) is at least one selected from an oxide, hydroxide and carbonate of a multivalent metal selected from zinc, magnesium and calcium. 
     
     
         3 . The coating solution for gas barrier according to  claim 1 , wherein the multivalent metallic compound (B) is at least one type selected from zinc oxide and magnesium oxide. 
     
     
         4 . The coating solution for gas barrier according to  claims 1 , wherein the polymer including a carboxyl group is at least one type selected from a homopolymer and copolymer of monomer selected from acrylic acid, methacrylic acid, maleic acid and itaconic acid. 
     
     
         5 . A gas barrier laminate, comprising a substrate and a gas barrier layer provided on at least one surface of the substrate, wherein
 the gas barrier layer includes a coat layer formed from the coating solution for gas barrier according to  claim 1 .   
     
     
         6 . A packaging material including the gas barrier laminate according to  claim 5 . 
     
     
         7 . A packaging material for heat sterilization including the gas barrier laminate according to  claim 5 .