COMPOSITE FILM OF POLYPARABANIC ACID

摘要

PURPOSE:To enhance bonding strength, heat resistance and electric insulating properties of the film by laminating fluoroplastic to a polyparabanic acid film whose surface is fluorinated by plasma treatment using fluorine gas. CONSTITUTION:The surface of a polyparabanic acid film is fluorinated by plasma treatment using fluorine gas and fluoroplastic is laminated to the treated surface of the film. PPA constituting the polyparabanic acid film is a synthetic resin represented by formula 1 [wherein R is a divalent org. group] and usually obtained by reacting hydrogen cyanide with diisocyanate represented by general formula OCN-R-NCO [wherein R is a divalent org. group] or can be prepared by hydroyzing a polymer represented by formula 2 or 3. In the surface fluorination of the PPA film, a high frequency electric field is applied to fluorine gas to generate plasma and the surface of the PPA is fluorinated by a large number of the radicals generated in the plasma. As the fluorine gas, DF4 or CHF3 is designated.