A method for producing a branched-polyether resin composition of the
present invention includes a first step of obtaining a reaction mixture
including: (1-A) a branched-polyether resin (X) containing a hydroxyl
group, an acryloyl group, and an epoxy group and (1-B) at least one resin
component selected from the group consisting of (1-B-1) a diacrylate
(A2) of an aromatic difunctional epoxy resin, (1-B-2) a monoacrylate (A1)
of an aromatic difunctional epoxy resin, and (1-B-3) an aromatic
difunctional epoxy resin (B) other than (A1) and (A2); and a second
step of mixing the reaction mixture and an unsaturated monocarboxylic
acid, and reacting the epoxy group in the reaction mixture and a carboxyl
group in the unsaturated monocarboxylic acid.