BARRIER COATING COMPOSITION WITH ORGANIC PARTICLES

摘要

A moisture vapor and oxygen transmission resistant flexible film has a polymeric base layer and a barrier layer of discrete particles of a first organic polymer dispersed throughout a matrix of a second organic polymer. Preferably, the first and second polymers are water insoluble and water soluble, respectively. The barrier layer is formed by depositing onto the base layer a coating composition of finely divided insoluble organic polymer particles suspended in an aqueous solution of the water soluble organic polymer, a crosslinking agent and surfactant. The coating composition is heated to crosslink the barrier layer polymers and evaporate solvent to provide a barrier film suitable for packaging applications. Optionally, the film can be metalized to increase barrier properties.