Plastic parts repair coating technology spray coating process operation

Plastic parts spraying process for the operation of the plastic surface coating must have two basic conditions: First, good adhesion; Second, the coating can not be too much dissolution of plastic surface. Most hard plastic without primer, the top coat will be able to adhere well to its surface; in the semi-rigid plastic paint layer need to add flexible agent, can make the paint layer in the matrix expansion has a certain deformation capacity Without falling off or cracking. For the plastic parts of the spray, it is best to use a set of manufacturers to provide supporting materials, such as flexible agent, topcoat, the coating material, dilution agent and thinner.

1. the spraying of hard plastic parts

1.1 Internal spraying of hard plastic parts

Hard plastic parts generally do not need to spray primer and putty; internal plastic parts of the color of the paint by the body code on the decision to adjust the license, the main paint with acrylic paint. Each large paint factory provides the user with an internal paint chart, including the internal paint supply number, name, gloss and adjustment number. Internal hard plastic parts painting method is as follows: ① with a solvent cleaning plastic surface; ② by adjusting the number of general internal acrylic paint; ③ the required time to dry paint layer, and then loaded into the car.

1.2 Spraying of external hard plastic parts

External hard plastic parts generally do not have to spray the primer can be sprayed finish, but there are individual manufacturers recommend spraying a layer of primer and then spray the case of paint, no matter what the situation, spray the same way: ① with a cleaning agent Clean the surface of the parts thoroughly; ② spray the appropriate color of the finish; ③ to be completely dry paint, then the parts loaded to the car; ④ glass fiber parts before painting, paint should be putty and then sprayed in accordance with the method of steel plate spray surface paint. Before the local injection of hard plastic parts, which have been sprayed with aerosol compounds, a layer of adhesion promoter should be sprayed. Operation with 400 # wet sandpaper to burn the damaged parts, and then coated with primer, coated with adhesive and then spray paint.

2. flexible plastic parts spraying

Most flexible plastic parts of the paint layer need to join the elastic agent, so that the paint will not crack in the deformation, joined the elastic agent paint called elastic paint, the spraying method is as follows: ① sandpaper with 400 # Surface, and cleaning the entire surface with a detergent; ② in accordance with the provisions of the manufacturer, the primer, elastomer and solvent mixed together, the first primer mixed with the elastic agent, and then according to the temperature of the workshop by adding the right amount of solvent; The spray gun pressure adjusted to the specified value, spraying a sufficient amount of double-layer wet coating in order to completely cover the surface; ④ primer drying 30 ~ 60min, and then spray bright layer, to be dry, the car used.

3. plastic parts spraying example

Polypropylene bumper coating, for example, this plastic parts painting, because this plastic is very hard, you should first spray a layer of special primer inside the polypropylene paint, and then spray paint, the specific spraying process is as follows: ① with Solvent cleaning the surface; ② according to the requirements of the manufacturer, after spraying the diluted, mixed homogeneous polypropylene primer, dry 1 ~ 2h, and then spray the topcoat; ③ spraying the appropriate proportion of acrylic paint, dry 8h, to ensure that the hardening of paint; When using the bottom layer to brighten the paint layer, spray primer, dry and then spray acrylic paint, dry 15 ~ 30min, then spray bright paint layer; ⑤ damaged polypropylene bumper re-spraying process.