Photosensitive microcapsules having radiation absorbers associated therewith such that the sensitivity of the microcapsules is reduced over a portion of their spectral sensitivity range; the spectral sensitivity of the microcapsules is thereby adjusted such that three sets of microcapsules having distinctly...http://www.google.com.au/patents/US4576891?utm_source=gb-gplus-sharePatent US4576891 - Photosensitive microcapsules useful in polychromatic imaging having radiation absorber
