Release Developers

The leuco dyes of this new class are peculiar in that they are capped at their 10-position by another dye moiety. They are in fact colored leuco dyes which on oxidation are split into two different dye fragments one of the dyes is destined for the receptor sheet while the oxidized leuco hopefully remains on the donor sheet. The capping dye is selected among sublimable dyes whereas the azine dyes being cationic in nature would be less mobile. They have been developed to address some problems encountered in thermographic and photothermographic systems.24 Representative examples of this class of leuco dye developers are compounds 65, 66, and 67. 

The characteristics of the azine leuco dyes have been adapted to the development of this new class of leuco dye developers. Sublimable or diffusible dyes are used to cap the 10-position of the leuco thiazine, oxazine, or phenazine dye where the splitting takes place as a result of imaging. The leuco dye moieties are rendered less mobile with long aliphatic chains. 

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Azure A can be reduced to an air sensitive intermediate 71 and acylated in one step to produce the ballasted leuco 72 which can be isolated and capped with the dye chloroformate 69 to give the ballasted yellow dye release developer 73. 

Dye release developers are themselves colored molecules, the presence of which in silver halide photographic materials could interfere with light capture by the light-sensitive silver halide. Less light would be available to the sensitizing dyes. Another approach has been reported in which the leuco dye is linked to the coupling-off position of conventional photographic color... 

Conditions Release Type Release Development Hazard... 

Elucidation of the primary structure of PBAN opened up a new field of research with immense possibilities. The exact site and the specific neurosecretory cells that produce PBAN need to be identified. We also need to determine where, when, and how PBAN is released. Development of antibodies for their use in immunohistochemistry should prove useful. A radioimmunoassay for PBAN will be useful to more precisely detect the hormone in various tissues such as hemolymph, and follow the time-course of release and determine PBAN titer at various times of the day. Identification of the receptors for PBAN is crucial to the study of its mechanism of action (how does PBAN induce pheromone production ). 

Provide accurate and reliable data to support product release, development activities, or submissions to the regulatory authorities, and... 

The generic approach to airborne release development was that approach used by DOE in developing the HC2 threshold quantity for each isotope as described in Attachment 1 of DOE-STD-1027-92, Change 1 (DOE, 1992). DOE developed a set of final release fraction values (FRFVs) for the various physical forms of materials that could be present in a facility. These FRFVs were used to reduce the quantity of radioisotope materials at risk for airborne release from the facility in an accident situation. The FRFVs were intended to address all of the uncertainties noted above on a facility wide basis. DOE noted that it was possible to calculate higher values for FRFVs for some physical forms and processes but that those processes were likely to be present on only a local and not a facility wide basis. Thus, DOE concluded the FRFVs were an adequate average for hazard categorization purposes. DOE used the FRFVs... 

Track the product after release developing an awareness of its strengths and weaknesses. 

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