Patent ID: 7390450

Claim:
A process for producing a fire resistant polycarbonate sheet, comprising: compounding an aqueous solution consisting of an organic flame retardant salt with a finished polycarbonate to form a fire resistant polycarbonate, wherein shear is applied during the compounding, and wherein the organic flame retardant salt has a formula: [Y′(SO 2 ) z ] n Y″(SO 3 M) w , wherein M is an alkali metal or an alkali earth metal, Y′ and Y″ are an aryl radical of 1-2 aromatic rings or an aliphatic radical of 1-6 carbon atoms and may be the same or different, z is an integer between 0 or 1, n is an integer between 0 to 5, and w is an integer less than 6, wherein Y′ and Y″ together must contain at least one aromatic ring to which the SO 3 M group is attached; and extruding the fire resistant polycarbonate into the fire resistant polycarbonate sheet, wherein a number of surface inclusions in the extruded fire resistant polycarbonate sheet is reduced about 100 percent compared to compounding the flame retardant salt in solid form with the polycarbonate.