After the paint film dries, partial peeling occurs, and even the whole paint film detaches from the surface of the object to be coated, or separates from the primer and falls off, which is called peeling. The reason is:
(1) The surface of the object is not clean, such as stained with oil, water, scale, etc., the bottom layer is not firmly bonded to the surface, causing peeling off.
(2) The surface to be coated is too smooth, or the surface is not properly treated, and there is no rough treatment.
(3) The paint quality is poor, the paint contains rosin or the thinner is used too much, the adhesion is poor, and the paint film is prone to peeling over time.
(4) The two coats of paint do not match or the layers are stained and not completely dry, which may cause large areas of peeling.
(5) When baking, the oven temperature is too high or the time is too long.
(6) Use oily putty as the bottom layer to seal. If there is too much oil in the putty and the topcoat is applied before it is completely dry, the bottom layer will crack due to expansion and contraction over time, which will affect the adhesion of the topcoat film and cause peeling.
(7) Before the putty is embedded on the plastered wall of the cement type, the oil is not brushed, and the oil absorption of the bottom layer is strong, and the oil of the putty and each layer of paint is absorbed more, and it is easy to fall off after the film is formed.
To sum up, to avoid paint peeling, oil stains, turpentine, etc. on the surface of the object should be effectively cleaned before painting. When painting on the wall, you must first brush the oil once, and then insert putty. Adding anti-aging agent to the paint can prolong the service life and prevent peeling.
If the paint film is completely peeled off, the paint film should be scraped off and repainted.
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