Pyrocatechin or Pyrogallol were used in commercial MQ developers by Ilford and also Kodak to extend the life as well in D&P developers.
Adding: In a 1941 BJP article on the modern uses of Pyro developers there's a section on the MQ developers like D75 and D75b which include Pyro. The Pyro acts as an oxygen absorber someting that had been know bu then for some time according to the article.
Of all the dev ingredients I could imagine for a long shelf life and long tray life developer, ascorbic acid is about the last one I would pick ... even if you pick a suitable sequestering agent (i.e. not Calgon) to capture all the iron, aerial oxidation must still be reckoned with.
Originally Posted by Nicholas Lindan
"... the ability of borate ions to form stable molecular complexes with compounds containing hydroxyl groups on adjacent carbon atoms. Thus catechol and pyrogallol or certain of their derivatives should not be used in developers based on borates." Mason, p 34. The developing capability of catechol is almost completely eliminated and that of pyrogallol seriously reduced. Of course this does not apply to the metol in the PMK fgformula.
Originally Posted by Keith Tapscott.