The Development of DYLUX Instant Access Photosensitive Products

THE DEVELOPMENT OF DYLUX INSTANT ACCESS PHOTOSENSITIVE PRODUCTS 

A historical/technical treatment of the development of DYLUX 503 proof paper shows that there were a number of miss-steps or diversions, which, while enriching the technology, also seem to have been wasteful, in retrospect. This entire development was undertaken by chemists who had no experience in imaging technology this development was also a significant educational experience. 

However, the development of DYLUX proof paper, and the associated HABI chemistry was essential to DuPont s successful photopolymer products, which depended on the unique stability and versatility of HABIs. Had the DYLUX program been terminated before it was a commercial success, the essential o-chloro-HABIs would not have been available for subsequent products. 

DYLUX products were developed by the DuPont Company, employing research on hexaarylbiimidazoles (HABIs) started in the early 1960s by Cescon, Coraor and Dessauer. As reported elsewhere, the original impetus for work with HABIs was their photochromic behavior. The fatigue reaction of HABIs, inevitably lead to the reduction product triarylimi-dazole, suggesting that these compounds were excellent photo-oxidants. 

Years earlier, W. Balon and O. Stallmann et al. at DuPont had investigated stable derivatives of Leuco Crystal Violet in spirit duplicating processes. The latter were a popular and a rel- 

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The Development of DYLUx Instant Access Photosensitive Products... 

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