Ewesly / Holographic Formulae / GP 431
Bleach solution
300 mg Phenosafranine
150 g Ferric Nitrate
33 g Potassium Bromide
One litre water
Dilute 1 to 4 with water before use.
Processing
Bleaching time: One and a half times the time it takes to clear.
Temperature: 20C Agitation: Intermittent
For rehalogenation after fixing. Hans Bjelkhagen prefers this over the simpler GP 431 formulation for pulsed masters developed in Neofin Blau diluted 1:1.
Shelf life: This stock solution lasts indefinitely, working solution about one week.
Source: <a href="NickAdvances.PDF" title="The Origins of the Dreaded PBQ" target="_new">N. J. Phillips, A. A. Ward, R. Cullen, D. Porter, "Advances in Holographic Bleaches," Photographic Science and Engineering 24, 120 (1980). </a>
Also: <a href="../Developers/AgfaBrochure.PDF" title="Second Edition of the brochure" target="_new">Agfa Gevaert Technical Information Bulletin 21.7271(480).</a>
<a href="AgfaBrochure.PDF" title="More uselessness!" target="_self"></a>