抄録
We built as a trial an automatic measuring system of acid values of different varnishes, which can be used in a factory to decrease errors by a manual handling and simplify a titration work.
A change in colour with phenolphthalein at the end point of titration is read out as a change of voltage and the total volume of titrant is converted into the voltage by the operating circuit.
Acid values of benzoic acid, fatty acids, and alkyd varnishes were measured by our system and obtained results are more accurate than results by a manual method in the coefficient of variation.
