The slogan of CAE Div. is "The work is SDGs・CN (carbon neutral) efforts themselves," and one of these is the paint spray painting CAE using robotics for mass-production-produced cars. In order to achieve a uniform coating thickness and a good appearance, the coating is finished in good quality, with complex and difficult adjustments, such as the amount of paint discharged, the direction of ejection, the distance to be moved, and the speed, as a result of trial and error in the non-operating day of the plant. In order to reduce the number of such tries, we are working on technological developments and operations of painting CAE in order to replace them with digital preliminary investigations. As a consequence, we can contribute to reducing the use of paint and CO₂.