The Dow Chemical Company

Michiharu Matsuguchi

Norio Onofusa

Kazuhiko Hiyoshi

Tadao Nishikage

Norio Matsuura

An aqueous dispersion of vinylidene chloride resin which, when coated onto a synthetic resinous film substrate, has the combined properties of: (1) good adhesion to the substrate; (2) good adhesion of a printing ink to the coating; (3) satisfactory barrier to gases (especially oxygen) and water vapor; and (4) a high resistance to boiling water treatment. The vinylidene chloride resin must also have polymerized therein methyl methacrylate, methacrylonitrile and methacrylic acid. A total amount of methacrylic acid must be between 1.times.10.sup.-4 and 3.times.10.sup.-4 moles of methacrylic acid per gram of polymer solids. A portion of the total amount of methacrylic acid exists in a form titratable with a 1/20 Normal aqueous solution of sodium hydroxide. The portion must be the less of (a) about 1.3.times.10.sup.-4 moles per gram of polymer solids or (b) about 60 percent of the total amount.

Aqueous dispersions of vinylidene chloride resins

An aqueous dispersion of a vinylidene chloride resin which, when coated onto a synthetic resinous film substrate, has the combined properties of: (1) good adhesion to the substrate; (2) good adhesion of a printing ink to the coating; (3) satisfactory barrier to gases (especially oxygen) and water vapor; and (4) a high resistance to a boiling water treatment. The dispersion must also contain an unsaturated carboxylic acid in an amount of from about 0.5.times.10.sup.-4 to about 4.times.10.sup.-4 mol of unsaturated carboxylic acid units per gram of solids in the dispersion. The unsaturated carboxylic acid must have a partition coefficient of greater than or equal to 1. A limited portion of the amount of the unsaturated carboxylic acid is contained in the aqueous phase. The remaining unsaturated carboxylic acid is polymerized with the vinylidene chloride.

Growing community of inventors

Nobeoka, Japan

Michiharu Matsuguchi