Painting is the general term for surface coating processing of industrial products. It is generally used for plastic oil spraying, silk screen printing and pad printing; Color change and screen printing of EVA, rubber and other shoe materials. An injector is required to complete this process. You can choose oil to spray matt, semi matt, high gloss, etc. according to your needs.
Why spray oil?
Fuel injection on the surface of the hand board can make it more beautiful. To some extent, the extreme fuel injection effect can make consumers have a better visual impact and promote consumption. Moreover, oil spraying has a certain protective effect on the hand board and products. Take the painting of metal surface as an example. The painting of metal surface is a method to protect the metal from oxidation and corrosion. Good paint coating protection layer shall be continuous, intact and well combined, and can become a barrier to inhibit the invasion of corrosive media.
There are five processing steps for fuel injection:
1. Annealing: The plastic is easy to form internal stress during molding, and the stress concentration is easy to crack after coating. Annealing treatment or full face treatment can be used to eliminate stress. The annealing treatment is to heat the ABS plastic molding parts to the temperature below the thermal deformation temperature, that is, 60 ℃, and keep the temperature for 2h. Since this process requires a large amount of equipment investment, the whole surface treatment technology can be used, that is, the solution that can eliminate the internal stress of the plastic part can be configured to treat the surface of the plastic part for 15-20 minutes at room temperature.
2. Degreasing: The surface of plastic parts is often stained with oil stain, hand sweat and release agent, which will make the adhesion of paint worse, and the coating will crack, bubble and fall off. Oil removal treatment shall be carried out before painting. The plastic parts are usually cleaned with gasoline or alcohol. After chemical degreasing and chemical degreasing, the residual lye on the surface of the workpiece shall be thoroughly cleaned, and finally cleaned with pure water, dried or dried.
3. De electrification and dedusting: plastic products are insulators, and the surface resistance is generally about 1013 Ω, which is easy to generate static electricity. After electrification, it is easy to absorb fine dust in the air and attach to the surface. Because it is very difficult to remove the electrostatic adsorbed dust with the general air blowing method, it is better to use high-pressure ionized air flow to simultaneously remove the electrostatic dust.
4. Spraying: the thickness of plastic coating is 15-20 μ m. It usually takes 2 to 3 coats of paint to finish. The second spraying shall be carried out after the first spraying is dried for 15min. The surface that needs to be bright must also be sprayed with transparent paint. The coated parts have little effect on the flame retardancy.
5. Drying: generally, paint is baked at 150-180 ℃ for 20-30 minutes; Bake plastic paint at 60-80 ℃ for 20-30 minutes; Some special paints can be dried under the greenhouse.