The extraordinary mechanism underlying the ferric gum process
Michael Andrews explains some of the technical details of the ferric gum process.
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Ferric gum process – a radically different variation on gum
The ferric gum process is like gum bichromate in some respects but it is also radically different. Sensitiser is brushed onto the paper, the paper is dried and exposed under a suitable image, and only at this point would pigmented gum be brushed onto the exposed paper.