Masking problem - white hair with a smile

whitening

Whitening, also known as fogging, results in a cloudy or milky white coating that often forms a fragile semi transparent film after drying.

① Excessive temperature or humidity can cause whitening. When operating in an environment with air humidity exceeding 80% and temperature above 30 ℃, the low boiling point solvent in the coating rapidly evaporates and absorbs a large amount of heat, causing the temperature of the coating to be lower than room temperature, causing water vapor in the air to condense on the coating and turn milky white due to water oil incompatibility. The most sensitive to this is nitro coating‘

If operated in rainy, cold, or windy environments, it can also cause whitening. The method of prevention is to maintain the temperature and humidity specified by the process in the operating area; High boiling point solvents such as butyl acetate and pentyl acetate can also be added as moisture-proof agents; Alternatively, the workpiece can be heated and then coated with a gloss film.

② Moisture mixed into the paint can also cause whitening.

③ The ratio of dilution hood gloss coating is improper.

④ There is moisture in the air storage cylinder during spraying.

Laugh

The masking film on the surface of the workpiece is partially unable to adhere and shrinks to form jagged or bead like spots, exposing the underlying layer, resembling the facial patterns seen when people laugh.

① The surface of the workpiece is contaminated with water, dust, or oil stains.

② A surface that is too smooth can also cause laughter defects.