Abstract: An esterification reaction product obtained by esterifying dipentaerythritol and a 12-hydroxystearic acid polymer and having a hydroxyl value of 20 to 70 mg KOH/g and an acid value of 3 mg KOH/g or less. The esterification reaction product has a high-water holding property and a pigment-dispersing property.

Abstract: [Object] To provide an esterification reaction product having high water-holding properties and pigment-dispersing properties. [Solving means] The esterification reaction product according to the present invention is obtained by esterifying dipentaerythritol and a 12-hydroxystearic acid polymer and has a hydroxyl value of 20 to 70 mg KOH/g and an acid value of 3 mg KOH/g or less.

Abstract: Provided are a dispersion excellent in the dispersibility of powder particles, dispersion stability, storage stability, and versatility; and a cosmetic blended with such dispersion. An oil dispersion of a surface-treated powder, comprising a surface-treated powder coated with a half ester oil, and a lipophilic solvent as a dispersion medium, wherein the half ester oil comprises an ester compound having 16 or more carbon atoms in total as can be obtained by reacting at least one kind of alcohols having 1 to 36 carbon atoms with at least one kind of carboxylic acids having 1 to 36 carbon atoms, and wherein the half ester oil has an acid value of 15 or more.

Abstract: Providing a surface-treated powder coated with a half ester oil, wherein the half ester oil contains an ester compound with 16 or more carbon atoms in total, as obtained by reacting one or more alcohols with one to 36 carbon atoms with one or more carboxylic acid with one to 36 carbon atoms and wherein the half ester oil has an acid value of 15 or more. The surface-treated powder of the invention has excellent adhesion to and spreadability on skin and hair, excellent dispersibility in general oils such as ester oil and triglyceride and in silicone-series or fluorine-series oils, and moist feel.