Does a white car showing black indicate exposed primer?
2 Answers
When a white car reveals black, this black color is the primer. At this point, it should not be left unattended. Over time, the scratched area will rust and gradually expand, requiring more effort to repair later. Additional information: 1. The role of automotive primer: Automotive primer is the first layer of paint directly applied to the surface of treated vehicle components, marking the beginning of the entire coating. It is designed to have excellent adhesion to the substrate, good compatibility with the intermediate or topcoat layers above, and must also possess strong anti-corrosion, anti-rust, oil resistance, chemical resistance, and water resistance properties. 2. Requirements for automotive primer: Depending on the application area on the vehicle, automotive primer must exhibit excellent adhesion to the substrate, good compatibility with the intermediate or topcoat layers above, and must also provide strong anti-corrosion, anti-rust, oil resistance, chemical resistance, and water resistance properties. Additionally, the film formed by the automotive primer should meet mechanical performance standards such as hardness, gloss, flexibility, and stone chip resistance.
I've been pondering this issue for quite some time. If a white car shows black, it definitely means the primer is exposed. The structure of automotive paint generally consists of three layers: the bottom layer is the primer, which is darker in color (such as black or gray) and mainly serves as rust protection; the middle layer is the base coat, which is the white layer that gives the car its color; and the top layer is the clear coat, a transparent protective layer. A white car showing black indicates that the base coat has worn off, exposing the primer layer directly. This is usually caused by minor scratches, improper car washing, or natural aging. If not repaired promptly, the exposed metal parts will rust faster, and once rust spots appear, they become much harder to deal with. I once scraped my car against a wall corner while parking and ignored it, only to find rust pits appearing on the body after the rainy season. Fixing it turned out to be costly and labor-intensive. My advice is to take it to a paint shop as soon as you notice the issue. The cost depends on the size of the affected area—small shops might charge around 100-200 RMB. Also, try to wash your car gently to avoid such damage in the future.
