VORRICHTUNG ZUM REGELN DER KONZENTRATION EINER FLUESSIGEN LOESUNG

摘要

A reserve supply of diazotype developing liquid from which liquid is supplied to semi-dry diazotype developing apparatus is maintained at both a substantially constant level and the required concentration of azo coupling component by introducing solvent for the liquid to restore the liquid level upon a decrease of the supply volume, sensing the specific gravity of the supply liquid by a hydrometer, and counteracting the decrease of concentration resulting from solvent addition by introducing a liquid concentrate containing the azo coupling component and electrolyte in response to a lowering of the hydrometer.