| abstract |
A water-soluble film comprises a polyvinyl alcohol resin (A), wherein a difference (ΔR) between a phase retardation (Rα) of one of opposite surfaces (α surface) of the water-soluble film and a phase retardation (Rβ) of the other surface (β surface) of the water-soluble film is not greater than 8 nm as measured on a middle portion of the water-soluble film with respect to a transverse direction (TD) of the water-soluble film. Therefore, the water-soluble film has a reduced difference in crystallinity between the front and back surfaces thereof and, hence, is less liable to be curled to thereby ensure a higher productivity. |