The Nippon Paint Holdings Group has developed a water-based base paint that enables continuous coating as an automotive repair paint. Compared to conventional solvent-based paints, water-based paints are characterized by slow evaporation of water, and it is difficult to increase viscosity during coating. Thus, water-based paints were likely to cause sagging and unevenness, and it was difficult to perform recoating (continuous coating) without pre-heating. We have achieved atomization performance during spray coating and ensured viscosity recovery after coating by using a paint viscosity design that imparts the shearing speed dependency.

The administrative jurisdiction of laws and regulations that affect the automotive sheet metal coating industry has been shifting from the Ministry of the Environment (in charge of the environment) to the Ministry of Health, Labour and Welfare (in charge of health and safety). Due to the decrease in the number of vehicles repaired in the market and a chronic shortage of human resources, the industry is required to improve productivity, increase profitability, create a reliable working environment, and develop human resources. The water-based paints of the Nippon Paint Holdings Group, which are developed by applying this technology, significantly reduces VOCs compared to solvents. The CO2 emissions (energy consumption for heating of booths, use of coating guns, and ventilation) have been reduced compared to those of conventional water-based paints. The work time is also comparable to that of solvent-based paints because continuous coating is possible. These water-based paints meet various laws and regulations and ensure productivity.