Photographic development reaction

In most color photographic products, organic compounds such as couplers or redox dye releasers are added to the melted emulsions before coating. These compounds are essential to the development reactions that produce the dye molecules composing color images. 

Some of its compounds, particularly the oxides, are used in chemical industries as catalysts to speed up organic chemical reactions. The yellow-brown vanadium pentoxide (V O ) is used as a catalyst to facilitate the production of sulfuric acid by the contact process. Vanadium pent-oxide is also used as a photographic developer, to dye textiles, and in the production of artificial rubber. When combined with glass, it acts as a filter against ultraviolet rays from sunlight. 

Hydroxylamine hydrochloride is used for controlled reduction reactions. It is used in organic synthesis as an antioxidant for fatty acids and in photographic developer solutions. 

Lithium hydroxide is used as an electrolyte in certain alkahne storage batteries and in the production of lithium soaps. Other uses of this compound include its catalytic applications in esterification reactions in the production of alkyd resins in photographic developer solutions and as a starting material to prepare other lithium salts. 

A variety of compounds are used as photographic developing agents. They are not all arenediols. In fact, most are aromatic aminoalcohols or diamines, but irrespective of their structural differences, they all possess the ability to undergo redox reactions of the type described for 1,4-benzenediol. Structural formulas and commercial names for several important developers are... 

Devise syntheses from benzene of each of the photographic developers whose structure is shown in Section 26-2C. Some reactions you will need are discussed in Chapters 22 and 23. 

See other INDUCTION PERIOD INCIDENTS, REDOX REACTIONS Photographic developer... 

Salts of [Cr(bpy)3] + are best prepared by chemical or electrochemical oxidation of chromium(II) systems (857). Care must be taken to minimize redox reactions that give rise to [Cr(bpy)2L2] + (52, 75, 219, 245, 589, 621, 721, 856, 857, 872, 917, 921). Salts of [Cr(bpy)3]2+ have been evaluated as photographic developers (741) and used for the reduction of the binuclear Fe, Fe center in hemerythrin (26, 27). A mass spectroscopic study of [Crfbpylsl salts has been reported (133). 

Use Organic synthesis, photographic developer, medicine, controlled reduction reactions, nondiscoloring short-stopper for synthetic rubbers, antioxidant for fatty acids. 

Other areas where L-ascorbic acid has found uses in industrial processes are, for example, in polymerLsation reactions, in photographic developing and printing, in metal technology, and even in intravaginal contraceptives. Most of these applications involve the use of the reducing properties of L-ascorbic acid in some way. 

Quinol is readily soluble in water, from which it crystallizes in prisms which melt at 169°. It can be sublimed unchanged. An aqueous solution of quinol slowly turns brown when exposed to the air and loses its reducing power. As a reducing agent it is intermediate between pyrocatechol and resorcinol. An alkaline solution of quinol is a valuable photographic developer. Oxidizing agents convert quinol into quinone the reaction will be considered later (577). When ferric chloride is added to an aqueous solution of the phenol. 

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