The Site of Reaction in Direct Photographic Development
- 1 September 1946
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 14 (9), 536-539
- https://doi.org/10.1063/1.1724190
Abstract
The rate of the silver‐catalyzed reduction of silver ions derived from soluble silver salts is directly proportional to the concentration of the hydroquinone when the latter is the reducing agent. The kinetics thus give no evidence that adsorption of hydroquinone by silver is a pre‐requisite for reaction. Similar results are obtained with catechol as reducing agent. The rate of development of silver bromide grains, on the other hand, varies approximately with the 0.6 power of the hydroquinone concentration (pH 8.0–8.9) and the 0.56 power of the catechol concentration (pH 7.7), indicating adsorption by the silver bromide or by the silver‐silver bromide interface region prior to reaction. This result is in contradiction with the ``electrode'' mechanism of development, but is in accord with the concept of a direct reaction between the developing agent and silver halide at the triple interface.Keywords
This publication has 9 references indexed in Scilit:
- The charge effect in relation to the kinetics of photographic development. I. The general effectJournal of the Franklin Institute, 1945
- Oxidation Processes. XV.1 The Effect of Reducing Agents on the Autoxidation of Some Photographic Developing AgentsJournal of the American Chemical Society, 1943
- Latent image formationTransactions of the Faraday Society, 1943
- Reduction of Silver Halides and the Mechanism of Photographic Development.Chemical Reviews, 1942
- Adsorption in Photographic Development. I. On the Non-Adsorption of Organic Developers to Metallic SilverJournal of the American Chemical Society, 1941
- Reduction of Silver Ions by Hydroquinone and p-Phenylenediamine in Alkaline Solution.The Journal of Physical Chemistry, 1941
- Mechanism of Photographic Development. II. Development by Hydroquinone.The Journal of Physical Chemistry, 1940
- The Reduction of Silver Ions by HydroquinoneJournal of the American Chemical Society, 1939
- On the adsorption theory of photographic developmentTransactions of the Faraday Society, 1938