Abstract: The invention is directed to a process for producing a plastic container with a barrier coating comprising a) applying at least one coating layer of a first polyvinyl acetal on at least a part of the plastic container; b) applying at least one coating layer of polyvinyl alcohol on the first polyvinyl acetal layer; c) applying at least one top coating layer of a second polyvinyl acetal on the polyvinyl alcohol layer. The surface of the plastic container may be pre-treated before coating. In addition to the barrier coating, the surface energy of at least a part of the inside surface of the plastic container may be increased by applying at least one inner hydrophilic coating layer.

Abstract: The invention is directed to a process for producing a plastic container with a barrier coating comprising a) applying at least one coating layer of a first polyvinyl acetal on at least a part of the plastic container; b) applying at least one coating layer of polyvinyl alcohol on the first polyvinyl acetal layer; c) applying at least one top coating layer of a second polyvinyl acetal on the polyvinyl alcohol layer. The surface of the plastic container may be pre-treated before coating. In addition to the barrier coating, the surface energy of at least a part of the inside surface of the plastic container may be increased by applying at least one inner hydrophilic coating layer.

Abstract: The invention is directed to a process for reducing the gas permeability of a plastic material by applying a barrier coating on the plastic material comprising the steps a) pre-treatment of at least a part of the plastic material; b) applying at least one coating layer of polyvinyl alcohol on the pre-treated surface and c) applying at least on top coating layer of polyvinyl acetal on the polyvinyl alcohol layer.