Aqueous latex of vinylidene chloride copolymer

An aqueous latex (latex (L)) of a vinylidene chloride copolymer (copolymer (A)), wherein the copolymer (A) consists essentially of:

• recurring units derived from vinylidene chloride (VDC) in an amount comprised between 89.0 and 91.0 wt % of the copolymer (A),
• recurring units derived from methacrylonitrile (MAN) in an amount comprised between 2.00 and 5.50 wt % of the copolymer (A),
• recurring units derived from at least one ionic comonomer (ICO) in an amount comprised between 0.5 and 1.4 wt % of the copolymer (A), and
• recurring units derived from methylmethacrylate (MMA) in an amount such that the total of recurring units of VDC, MAN, ICO and MMA is 100 wt %,
• wherein the ionic comonomer is selected from the group consisting of 2-acrylamido-2-methyl-1-propane sulfonic acid sodium salt, sodium 2-sulfoethyl methacrylate, sodium 4-vinylbenzenesulfonate and mixtures thereof,
• and wherein the latex (L) comprises at least one surfactant (surfactant(S)) in an amount comprised between 0.09 and 1.50 wt % of the copolymer (A).