Why does the car turn black after a slight scratch?
3 Answers
Because the paint has come off. Here is some relevant information about cars: 1. Definition of a car: According to the latest Chinese national standard "Terms and Definitions of Types of Automobiles and Trailers" (GB/T3730.1-2001), a car is defined as follows: A non-track vehicle powered by an engine, with four or more wheels, mainly used for transporting people and/or goods; towing vehicles that carry people and/or goods; or for special purposes. 2. Introduction to domestic car brands: Domestic car brands include Hongqi, Changan, Great Wall, Chery, Geely, Roewe, BYD, etc.
I've encountered this issue before too. The car turns black after a scratch because automotive paint consists of several layers: the outermost is the clear coat protective layer, followed by the colored paint layer, then the primer layer, and at the very bottom is the vehicle's metal or plastic body. If the scratch isn't deep, it might only remove the clear coat and colored paint, exposing the primer which is usually black because it contains anti-corrosion materials. In more severe cases, it can directly expose the black metal part, which oxidizes more easily and turns black. This is related to automotive painting processes - standard vehicle primers are uniformly designed in black for coverage and rust prevention. For treatment, I recommend quickly using polish to smooth out shallow scratches or visiting a professional shop for touch-up paint to prevent rust. When parking, be mindful of spacing and avoid tight spots, especially when turning around pillars in parking lots. Wash your car gently, avoiding hard brushes to minimize surface damage. Regular waxing can protect the paint surface, extend its lifespan, and reduce exposure risks.
I've been driving for many years, and once while reversing in the neighborhood, I scraped against a tree, leaving a black mark on the car instantly. That was actually the primer layer exposed after the colored paint was scratched off, with black being common because many car models use dark-colored primer materials for rust prevention. The reason isn't complicated—minor scratches damage the outer protective layer, exposing the original color beneath, and the black primer makes the scratch more noticeable. If not repaired promptly, rain or moisture can cause the metal to rust, and over time, the affected area may expand. I usually buy a touch-up pen to cover it temporarily and then go to a repair shop for a thorough fix when I have time. Remember to maintain a safe distance, avoid parking too close to walls or obstacles on the roadside, and installing anti-scratch strips can also reduce accidents. Don't ignore small scratches; early maintenance of the car paint saves both money and hassle in the long run.
