POLY(1,4-PHENYLENEAZINE N,N-DIOXIDE) - A RECYCLABLE MATERIAL FOR A SOLVENTLESS LASER-IMAGEABLE RESIST PROCESS

Upon heating under vacuum, poly(1,4-phenyleneazine-N,N-dioxide) depoly merizes to give 1,4-dinitrosobenzene which can be condensed onto a sui table substrate. The nature of the condensate is dependent on the subs trate temperature. At temperatures below -110-degrees-C the condensate can be monomeric, at about -50-degrees-C it is a mixture of dimer and oligomers, and at -20-degrees-C it is polymeric. Thick and thin films of the polymer can be rapidly prepared by volatilization of 1,4-dinit rosobenzene from the bulk polymer onto a substrate and allowing the co llected condensate to warm to room temperature. The resultant films ap pear to be stable indefinitely at room temperature and atmospheric pre ssure yet can be selectively removed from the substrate using a focuse d visible laser beam. After a suitable image-transfer process, the pol ymer is removed by heating to 100-degrees-C. The laser imaging, deposi tion, and final removal of polymer are all nondestructive, thermal pro cesses. Thus if a suitable vacuum chamber equipped with a cooling trap is used for this process, the polymer is 100% recyclable.