Silver halides, in photography

How can you explain the change in the colour of the silver halides with an increase in the atomic number of the halogen Compare the solubility products of silver halides and sulphide (see Appendix 1, Table 12). What anion is the most sensitive reagent for the silver ion What is the significance of silver halides in photography What substances are used in developing photographs ... 

The increasing use of digital cameras is likely to have the effect of considerably decreasing the use of silver halides in photography. 

Coordination chemistry is important not only in conventional silver halide-based photography but also in a variety of other imaging systems. This review covers the use of coordination com-... 

In a German patent (70GEP1930337) (Scheme 27) 2,4-dihydro-5-sulfonylamino-pyrazol-3-ones such as compounds 97a d, were characterized as useful color formers for purple dyes in silver halide color photography. They were prepared by heating... 

Na COj and Na2S with SO2 or from Na2S03 plus sulphur. Forms many hydrates. Used-in photography ( hypo ) because it dissolves silver halides. Also used in tanning, preparation of mordants, as a fermentation preventative in dyeing and in chemical manufacture. 

All the silver halides are sensitive to light, decomposing eventually to silver. In sunlight, silver chloride turns first violet and finally black. The use of these compounds in photography depends on this (see below). (All silver salts are, in fact, photosensitive—the neck of a silver nitrate bottle is black owing to a deposit of silver.)... 

The use of sensitizing dyes in photography has been the subject of many studies and constitutes. still now. one of the most studied areas in specialized periodic publications (125, 126) or in textbooks (88. 127). It can be ascertained that one hundred years after Vogel s discovery of spectral sensitization, the basic mechanisms of action of dyes on their silver halide support still remain not fully understood. However, the theoretical reasons explaining why among many other dye families practically only cyanine methine dyes appear to be spectral sensitizers (128) are better known. 

We start the discussion of the group (2) of photo-de-diazoniations in imaging processes by noting that, after silver halide photography, systems based on the photolysis of diazo compounds form the second most important group of imaging processes. 

Sensitization of ArNJ in spectroscopy 280 f. Serendipity, in scientific discoveries 213,217 ff. Silver halide photography 283 Spherands 294 f. 

Silver(I) does not disproportionate in aqueous solution and, in almost all its compounds, silver has oxidation number +1. Apart from silver nitrate, AgN03, and silver fluoride, silver salts are generally only sparingly soluble in water. Silver nitrate is the most important compound of silver and the starting point for the manufacture of silver halides for use in photography. 

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