Explanation

photographic materials with diazonium salt or diazo resin as photosensitizer. The photosensitive diazonium salt or diazo resin is mixed with a coupling agent (usually a phenolic compound), added with a adhesive, and coated on the support body to become a diazo photographic materials. The imaging process mainly includes two steps: one is that diazonium salt photosensitizer decomposes into nitrogen and colorless decomposition products under light; The other is that the undissolved diazonium salt and coupling agent react under alkaline conditions to form dye or dyestuffc images. The image color is different with different coupling agents. The above diazo salt photosensitive materials are widely used in engineering drawing reproduction, printing, microfilming, geological exploration, electronics and other fields. The spectral color sensitivity range of diazo salt photosensitive materials is generally 350~450 nm. Its resolution can reach more than 1000 line mm; This kind of photosensitive materials is friction resistant and easy to operate. It can also be a negative diazo salt photosensitive materials, which is the most widely used and most influential among non silver photosensitive materials. Its varieties include diazo copy paper, diazo copy film, etc. This kind of photographic materials has a very high resolution and can form various metal images, so it is mostly used for micro copying and recording.

Classification