▎ 摘　　要

NOVELTY - A dispersant comprises a copolymer comprising an acrylate structural unit (I), a vinyl-based structural unit (II), and an acrylamide structural unit (III). USE - Dispersant used in composition for forming conductive material slurry and paste used in positive electrode of energy storage device e.g. battery (all claimed). ADVANTAGE - The dispersant provides conductive material slurry and positive electrode paste having reduced viscosity, and resistance. DETAILED DESCRIPTION - A dispersant comprises a copolymer comprising an acrylate structural unit of formula (I), a vinyl-based structural unit of formula (II), and an acrylamide structural unit of formula (III). R -R ,R -R =H, methyl or ethyl; R =8-30C hydrocarbyl;and X =functional group contained in the monomer unit of homopolymer (II). (i) Functional group X1exhibits an adsorption rate of carbon material-based conductive material of 10.0% or more, preferably 12% or more. INDEPENDENT CLAIMS are included for the following: a dispersant composition, which comprises the dispersant; battery conductive material slurry, which comprises the dispersant, a carbon material-based conductive material, and a solvent; production of the conductive material slurry for battery, which involves dispersing each component in a mixture containing the dispersant, carbon material-based conductive material, and solvent using a media stirring type disperser; a positive electrode paste for battery, which comprises the dispersant, carbon material-based conductive material, positive electrode active material, binder, and solvent; and a positive electrode for battery, which comprises the dispersant for positive electrode of an electricity storage device.