A method for preparing a novel compound, i.e. a resinous material, characterized in that an epoxy compound is allowed to react with ammonium salt or a metal salt (for example, lithium salt, sodium salt, potassium salt, magnesium salt, etc.) of polyglutamic acid. The resulting reaction product is useful in a method for treating shaped materials especially polyester textiles. In this method the shaped materials are treated with the novel resinous material to improve the appearance and handling characteristics thereof. A process for providing a wooly finish on polyester textiles is characterized by treating textiles (including polyester knittings and mixed spun fabrics or knittings or mixed woven fabrics or knittings) in a bath of an emulsified mixed solution of an epoxy compound and a metal salt of polyglutamic acid containing a catalyst, and carrying out a heat-treatment of the resulted textiles after pre-drying.