Study On Preparation And Application Of Ethylene-diamine Tetraacetic Acid Ferric And Amine Solid Salt

Ethylene—diamine tetraacetic acid Ferric and amine { NH4FeEDTA} is an important branch of aminopohycarboxylic acid solicl salt. It is used silver halide photographic to photographic processing as bleach agent. Ethylene—diamine tetraacetic acid Ferric and amine is acted in photographic processing and bleached mechanism, analysed strong and weak of oxidation and stable function from structure , intrinsical superiority of bleach-fix and processing of high temperatures and high speeds and safe manufacture and apphy are discussed . In the compound the simplest technology is selected and least impurity is introduced into and catalysis agent chosen to make cut a reaction time down to suitability. The crystal way and dry way suitably are tried to find out. The solid salt fromed a certain number technological question and existed contradictory are solid. It is realized that essential leaps from liquid to solid salt. In surface characteristic test it broke free from convertions analysis and the salt intrinsic character is adopted and the analytic way of suitability the salt is studied and formed analytic way scientifically and accurately. For NH4FeEDTA solid salt that overall applied function test is carried on with a strip of negative and photographic paper.The test result shows that it is possible to from liquid salt to solid salt on the compound factors controlled and strict operated, matters remained stable and better reappear function and ratio is obtained over 90%. Not-appear one's crystallize in the enriched liquid.The acidity value well be from 5.5 to 6.5 of pH and the processing temperature well be from 35℃ to 41℃ in processing. The acidity and temperature value are better tolerance. In the processing test for strips of negative and photographic paper the bring the bleach action into full play and Leuco cyan dye and Retained silver are made within the ideal range. Processing time is shortened to 45 seconds and fulfilled high temperatures and high speeds requirements. In the dynamic processing the sensitive parameter remained stable. It is non-influence for development and fixing. It can achieve bleach-fix. it is safe for body and environment in compound and apply. It is a "green" bleach agent.