Reproduction paper coated with one or more diazo light-sensitive dyes to make direct positive color prints. Different colors are achieved by the use of different developers and dyestuffs, such as diazodiphenylamine sulfate (green) or diazodinitrophenol (yellow). Diazo prints, depending on the process, may either be developed under water or with ammonia fumes. Prior to the advent of large format digital copying machines, diazo copying was preferred over blueprints for technical drawings because of its fast, clean, positive image.
Synonyms and Related Terms
direct process paper; diazotype paper; Whiteprint paper
Resources and Citations
- Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
- The Dictionary of Paper, American Paper Institute, New York, Fourth Edition, 1980
- E.J.LaBarre, Dictionary and Encyclopedia of Paper and Paper-making, Swets & Zeitlinger, Amsterdam, 1969, p. 193.