Coating composition

Abstract

A coating composition including an ionic polymer (a), a hygroscopic agent (b) and a solvent, the hygroscopic agent (b) being a granular crosslinked product of a monovalent metal salt of a poly(meth)acrylic acid and being contained in an amount of 75 to 700 parts by mass per 100 parts by mass of the ionic polymer (a).

1 . A coating composition comprising an ionic polymer (a), a hygroscopic agent (b) and a solvent, the hygroscopic agent (b) being a granular crosslinked product of a monovalent metal salt of a poly(meth)acrylic acid and being contained in an amount of 75 to 700 parts by mass per 100 parts by mass of the ionic polymer (a). 
     
     
         2 . The coating composition according to  claim 1 , wherein the coating composition is used for forming a defogging film. 
     
     
         3 . The coating composition according to  claim 1 , wherein the coating composition is used for forming a water shut-off film. 
     
     
         4 . The coating composition according to  claim 1 , wherein the ionic polymer (a) is a cationic polymer (a1). 
     
     
         5 . The coating composition according to  claim 1 , wherein the ionic polymer (a) is an anionic polymer (a2). 
     
     
         6 . A coating formed on a surface of a base material, a coating comprising a matrix of an ionic polymer (a) and a hygroscopic agent (b) dispersed in the matrix, and the hygroscopic agent (b) being a granular crosslinked product of a monovalent metal salt of a poly(meth)acrylic acid and being contained in an amount of 75 to 700 parts by mass per 100 parts by mass of the ionic polymer (a). 
     
     
         7 . The coating according to  claim 6 , wherein the coating has a haze of 5% or less and a maximum surface roughness Ra (JIS B-0601-1994) of 0.1 μm or less. 
     
     
         8 . The coating according to  claim 6 , wherein the coating is used as a water shut-off film. 
     
     
         9 . The coating according to  claim 6 , wherein the coating is used as a defogging film. 
     
     
         10 . A method of forming a water shut-off film or a defogging film on a surface of a base material by applying the coating composition described in  claim 1  on the surface of the base material followed by heating to remove a solvent.