How long can plastic color matching apprentices learn?

Three days. Plastic color matching is based on three basic colors: red, yellow and blue, which are pleasing to the eye, meet the color difference requirements of color cards, economical and practical, and do not change color during processing and use. The technology of plastic color matching is not difficult. Apprentices have to study for three days. The premise is that the master teaches well and learns quickly, depending on how he understands it. If he doesn't understand, ask the master.