An object of the present invention is to provide a solution-type paint excellent in acid resistance or the like. Specifically, the present invention provides a solution-type paint comprising a polymer having an epoxy group and branched glutaric acid, a coating film obtained by curing the solution-type paint, a composition comprising a polyether having an epoxy group, a polyester having an epoxy group or a polyether/polyester (a polymer having an ether linkage and an ester linkage in a molecule) having an epoxy group and branched glutaric acid, and the like. Examples of the polymer having an epoxy group include a vinyl copolymer having an epoxy group, and examples of the branched glutaric acid include 2,4-dialkylglutaric acid.