Alkyl phenylglyoxylates as radical photoinitiators creating negative photoimages¹

Abstract

Alkyl phenylglyoxylates are shown to be efficient photoinitiators for acrylate polymerization. Benzoyl and phenyl radicals derived from intermolecular hydrogen abstraction are the initiating species. A negative photoimage system was developed based on this observation. The imaging material consists of a polymeric phenylglyoxylate initiator and to-be-crosslinked diacrylate monomers. The contrast and sensitivity of this system have been measured.

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