Abstract: In this paper, two unblocking courses of the ether blocked-couplers in negative diazo type film have been studied by GC/MS analysis.UV-Vis.absorption spectra of imagingfilms have been measured and the photo-sensitive characteristic curves have been discussed.Results showed that the negative film based on the acid-induced rearrangement of blockedcoupler is more photosensitive than the film based on the acid-induced cleavage in theimaging process.The maxinum absorption peak of the former image is shifted towards longer-wavelength.

Key words: diazo process, diszonium compound, negative-working material, blocked-coupler