Details:
Summary:
After dealing with the traditional pressroom method of (chemical) control of acidic lithographic fountain solutions the contribution is concerned with a system based on the electrical conductivity of advantageously buffered fountain mixes. Detailed basis of the above is given with that of a non-subjective comparative system using purpose designed instruments suited to pressroom conditions and the responses of everyday dilutions of buffered concentrates. Data is shown in respect of a representative range of lithographic chemicals and concentrates as well as isopropanol and Techfount. It is suggested that standardized (constant pH) acidic fountain solutions, and a standard control system are feasible. Accuracy is achieved via monitoring instruments.