Лако-красочные материалы — производство

Various aspects of silver halide photographic theory and practice are discussed in many textbooks notably the Mees and James series.579 Al­though a three-color system can be designed based on three tetrazolium salts that would lead to yellow, magenta, and cyan formazan dyes, there is only one reference to such a system, involving the use of cyanide ions.580 However, the principle is utilized to produce dye-enhanced silver im — ages.581,582 The incorporation of tetrazolium salts in the photographic processing solution leads to more rapid processing,583,584 which may arise from the tetrazolium salt acting as an electron transfer agent or preventing the buildup of reducing agents.582 The acceleration in processing is also seen when the tetrazolium salts are incorporated in the photographic emulsion. This generally leads to high-contrast materials, useful in the production of lithographic plates.585-594 Tetrazolium salts also impart increased stability to these compositions against a number of environmental conditions.595- 607