Impermeable coatings

摘要

1,105,102. Coated substrates. SOLVAY & CIE. 16 May, 1966 [19 May, 1965], No. 21560/66. Headings B2E and B2K. A process for producing an impermeable coated support comprises applying to a support from aqueous emulsions a coating comprising at least two copolymers of vinylidene chloride wherein at least one of these copolymers (a) is an internally plasticised copolymer of vinylidene chloride and vinyl chloride which has a weight ratio of vinylidene chloride to vinyl chloride between 0.6 and 4 and which contains (in polymerised form) 1 to 100 grams per kilogram of one or more monomers having a plasticising character, the plasticising monomer (or each plasticising monomer if there are more than one) being an ester derrived from an unsaturated mono- or polycarboxylic acid and a saturated alcohol containing 4 to 18 carbon atoms or a vinyl ester of a saturated carboxylic acid containing 6 to 18 carbon atoms, or a mixture of such esters and wherein at least one of the (b) copolymers is a copolymer of vinylidene chloride in which the weight ratio of the vinylidene chloride to the comonomer(s) being between 4 and 49, the (or each) comonomer being acrylonitrile, methacrylonitrile or an ester derived from an unsaturated mono- or poly-carboxylic acid and a saturated alcohol containing from 1 to 4 carbon atoms, the emulsions being applied together or (a) being applied before (b). Specifield supports are paper, cardboard, pasteboard, plywood, leather, knitted fabric, woven fabric, rubber, regenerated cellulose and resinous materials. A plurality of layers of (b) may be applied.