The Chemistry of Mordançage, a Historic Photographic Process

Autor:	Rebecca M. Jones, Caroline Fudala
Rok vydání:	2019
Předmět:	Chemistry Mordançage chemistry.chemical_element Chloride Chemical reaction Copper Analytical Chemistry Acetic acid chemistry.chemical_compound Chemical engineering Emulsion medicine sense organs Hydrogen peroxide medicine.drug Photographic paper
Zdroj:	Analytical Chemistry. 91:14482-14488
ISSN:	1520-6882 0003-2700
DOI:	10.1021/acs.analchem.9b03205
Popis:	Based on a 19th century method, the process known as mordançage has been used to dramatically alter black and white photographs since the 1960s. Mordançage subjects a fully developed photograph to a series of wet chemical reactions, beginning with an acidic copper(II) chloride and hydrogen peroxide bleaching solution. Different types of photographic paper, time in mordançage solution, and the concentration of hydrogen peroxide, copper(II) chloride, and acetic acid are all variables that influence the degree of emulsion lift and corresponding veils observed. We conducted experiments to explore these variables and analyzed processed prints using ImageJ to measure changes in pixel intensity and SEM-EDS for compositional analysis. Fiber-based and cotton rag papers resulted in more emulsion lift than resin-coated paper, and increased time in the mordançage solution had similar results. Quantitative analysis of the bleaching solution reveals how the process variables affect the formation of veils, and a process scheme is presented. This work provides insight into the chemical transformations involved in this artistic process.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8532cbbc1884f91a9534a51ebe41e21a https://doi.org/10.1021/acs.analchem.9b03205 Zobrazit plný text záznamu