PURPOSE: To enhance dynamic characteristics and to reduce curling tendency and to improve adhesive and antistatic characteristics by using a polyester support having a specified glass transition point and heat treating it in a specified temperature range.

CONSTITUTION: The polyester support to be coated with a silver halide emulsion layer has a glass transition point Tg of 90-200°C and it is coated with an undercoating fluid and dried and then, heat treated at a temperature of 50°C-Tg. This polyester support is composed essentially of naphthalenedi-carboxylic acid and ethylene glycol, preferably, polyethylene-2,6-carboxylate. The undercoating fluid is a hydrophilic resin solution containing a phenol derivative polyester solvent or lubricant and at least one of carboxylic acids or anhydrides and a copolymer of vinylidene chloride and a vinyl monomer having a carboxylic group.