Development of surface preparation process before painting in plastic parts

In this study, the effect of surface preparation processes and the parameters used in plastic injection method on the surface energy of plastic parts were investigated. First, four different injection parameters were determined. The designated parameters are injection pressure, injection speed, cooling time and ironing time. Three levels were determined in these parameters and experimental plan was established by using Taguchi Design of Experiment method. Secondly, the effect of baking, alcohol wiping and dry ice cleaning processes before painting were investigated. For this purpose, the parts produced with nominal process parameters are used. The surface energies of the test pieces produced in accordance with the determined experimental plan were measured. Finally, experiments were carried out at different scanning distances and velocities to determine the effect of plasma and flaming methods in atmospheric pressure used to increase surface energy. Surface energy measurement test inks were used for measurement. In experimental data, low injection pressure and injection speed were found in parameter values and dry ice cleaning method was used in pre-painting methods.