METHOD FOR MEASURING CONCENTRATION OF NONVOLATILE COMPONENT OF ELECTRODEPOSITION PAINT

PURPOSE:To enhance the reliability of the results of measuring the concn. of the nonvolatile component in an electrodeposition paint and the ratio of the pigment component and resin component therein obtd. by measuring the ultrasonic attenuation rate of the electrodeposition paint in the state in which the pH, temp. and org. solvent concn. of the paint are within prescribed ranges. CONSTITUTION:The electrodeposition paint contg. the pigment component and resin component as nonvolatile matter is irradiated with ultrasonic waves and the ratio between the pigment component and the resin component is determined by utilizing the attenuation phenomenon. The irradiation with the ultrasonic waves is executed in the state in which the electrodeposition paint is within the prescribed ranges of the pH, temp. and org. solvent concn. The quantitative relations between the concn. of the nonvolatile component and the ultrasonic attenuation rate are previously obtd. with each of the plural electrodeposition paints varying in the pigment component and the resin component and are collated with the results of the measurement. The ratio of the pigment component and the resin component in the electrodeposition paint to be detected is thus known with the high reliability.