Polystyrene packaging material - coated with polyvinylidene chloride and of improved imperviousness to gases and vapours

摘要

Polystyrene articles used for packaging, esp. foodstuffs sensitive to oxidation or moisutre, are rendered imprevious to gases, vapours, ois, etc., by immersing the articles in a suspension of (co)polymers of vinylidene chloride in a solvent inert ot polystyrene, usually an alcohol, pref. nethanol, and evaporating the solvent at a temp. below the thermal deformation temp. of polystyrene, leaving a coating of the PVC.