The hypothesis is that the effect of acceleration by a quaternary salt is greater on the development rate of the divalent ion than on the rate of development of the monovalent ion of hydroquinone. The gross rate of development of a hydroquinone-sulfite developer was determined with and without a quaternary salt for a range of pH values. Comparison of the acceleration of catechol which is active as a monovalent ion with the acceleration of hydroquinone which is active mainly as a divalent ion was hoped to allow the separation of the hydroquinone gross rate into the contributions by the monovalent ion and the divalent ion. The quaternary salt complexed with catechol to form an insoluble salt making comparison of the acceleration effect not possible. Chlorohydroquinone was chosen and the rate of development with and without the quaternary salt was determined for a range of pH values. Separation of the contributions proved not to be possible so the hypothesis could not be tested. Over the pH ranges (9.25-10.35 for hydroquinone and 8.33-9.16 for chlorohydroquinone) the gross rate of development showed linearity (on log-log scale) with the monovalent ion and the divalent ion concentrations but was determined to be dependent only upon the divalent ion concentration for both developing agents whether unaccelerated or accelerated developers. Diffusion effects were important with the accelerated developers because of the high rate of development. The quaternary salt caused a shift in the density-time curve for each developer solution to shorter times and also an increase in the slope past the induction period.

Library of Congress Subject Headings

Photographic chemistry; Photography--Developing and developers

Publication Date


Document Type


Department, Program, or Center

School of Photographic Arts and Sciences (CIAS)


Carroll, B. H.

Advisor/Committee Member

Francis, R

Advisor/Committee Member

Neuberger, D


Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: TR295.E74 1982


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