Water dispersion of vinyl halide copolymer and film

A water dispersion of a vinyl halide copolymer in which the vinyl halide copolymer satisfies all of the following conditions (1) to (3):

• (1) upon comparison of a chromatogram obtained through measurement by solvent gradient chromatography of a purified polymer obtained through purification of the vinyl halide copolymer by methanol precipitation and a chromatogram obtained through measurement by solvent gradient chromatography of a purified polymer obtained through purification of the vinyl halide copolymer by acetone precipitation, a peak I is present that only appears in the chromatogram for the purified polymer obtained through purification by methanol precipitation;
• (2) a detection time of a peak apex of the peak I is less than 9 minutes;
• and
• (3) the vinyl halide copolymer includes a polymer synthesized from a monomer group used as a raw material that contains a vinyl halide monomer and a copolymerization monomer having a reactivity ratio r1 with vinylidene chloride of less than 0.7, wherein a mass proportion of the vinyl halide monomer among 100 mass % of the monomer group is 60 mass % or more, and a mass proportion of structural units derived from the copolymerization monomer having a reactivity ratio r1 of less than 0.7 is 4 mass % or more relative to 100 mass % of total mass of the polymer.