In any case, before painting to degrease the surface to remove oil-grease. Too aggressive solvents are susceptible to damage solvents plastics. Degreaser to pick up such that-be do not dissolve very plastic, but it is well to remove impurities. The most 'gentle' is alcohol, not bad himself showed isopropanol, it is somewhat less volatile than ethyl alcohol, and do not drink! If contamination is strong, then degreasing should be done in two phases – first, rub the product with solvent dampened lint-free material, such as heavy-duty napkins resistant solvent radex absorbent blue, the second – rubbing dry material to remove contaminants. At one time to remove heavy contamination is not obtained, only spreads the product. If you use an antistatic degreasers, then simultaneously with the de-oiling we remove the static charge from plastic and reduces the likelihood of adhering dust. But if the production volume is large, and it becomes a problem – wipe each piece is individually words No! In this case, you need to think about degreasing equipment.
Solvents, plastic-soaked during the cleaning, must be completely removed before application of paints. Otherwise, do not evaporate before the end of degreaser can undermine the paint coating application. Immediately prior to coloring products can Blasting by compressed air, removing the solvent and residues and dust. When using a mixture of plastics be prepared to possible problems with the color of paint, not all materials are equally well hold for various plastics and besides, if a stranger appears on the surface of plastic products inclusions may arise craters as a result not of a homogeneous wetting of paint in these areas and on the main surface. Where possible, such products on the painting is better not to send, and if there is no other choice, then they should not be painted one normal layer, several thin deposition. With regard to dust I can only say one thing – if you want to have a quality color plastic, it is necessary to ensure that in the painting shop conditions and prevents the formation of a dust. But this is a subject of a separate article.