摘要 |
<p>The method of forming relatively thick deposits of polymeric material on a surface which comprises forming a thin coating on the surface of a solution of the polymeric material, at least partly drying the coating to eliminate some or all of the solvent for the polymeric material, applying a barrier coating to the polymeric material to protect it from attack by solvent, and applying a second thin coating of a solution of the polymeric material. The operation may be repeated as necessary to build up the required thickness of deposit. Coating is by successive immersions in baths of the polymeric solution separated by immersion in baths of the barrier material, or by other bulk treatment therewith, followed by partial drying before subsequent immersions and final drying after the last immersion.</p> |