Details:
Summary:
The quality of the raw water which is used to prepare fountain solution is a basic variable of the lithographic process. Experimental data have been presented, which show the effect of this variable on three attributes of typical acid and alkaline fountain solutions: pH, water takeup by ink, and corrosivity. The implications that these findings have on the control of fountain solution chemistry and press performance have been set forth as the main conclusions of this work. Other conclusions consist of criteria for judging when treatment of raw water is advisable, and recommended methods of treatment. A review of the fundamentals of fountain solution chemistry has also been included, along with the standard methods of characterizing raw water quality. In addition, the corrosivity of pure or high quality water has been explained in terms of modern corrosion theory.