How Does the Sun Damage Car Paint?
We’ve all seen a car lose its once-vibrant color after years exposed to the sun, but why does this happen? As it turns out, most car paint damage is due to the same component of sunshine that ages and damages our skin: ultraviolet (UV) rays.
UV light is invisible but very powerful. When it makes contact with a surface, that object’s molecules receive a jolt of energy. This extra energy is usually given off as heat, but some of these jolts result in molecular bonds breaking.
Over time, when this happens to enough molecules of paint, it no longer interacts with light in the same way. It becomes less reflective and duller, transmitting less light outward that we see as color.
Do Some Colors Fade Faster?
Regardless of UV intensity, some color paints are more susceptible to fading, with red paint usually losing its color the fastest. To understand why, we first have to understand that light comes in a spectrum of wavelengths, and how a material absorbs and reflects these wavelengths determines what color we perceive.
Every color has a specific wavelength, and a color paint is engineered to absorb all wavelengths except for the particular one or ones associated with its color blend. So red paint absorbs all wavelengths except those in the red band, which are reflected. We take in this reflected light, and if we aren’t color blind our eyes and brain combine to understand that light as red.
So why does red fade more than other paints? It’s because wavelengths associated with red are the lowest energy of visible light, so to appear red it’s absorbing much more energetic wavelengths, which causes more aggressive degradation of the paint’s molecular bonds. This is in addition to what UV rays are doing.
Protection Against Sun Damage
Because fading is caused by molecular breakdown there’s no way to reverse it, so preventative care is the best approach. Here are some tips on how to protect your car’s paint from sun damage.
Keep It Clean
By regularly washing your car, you can reduce the accumulation of other substances like pollution, as well as salt that can damage the paint molecules and accelerate fading.
Keep It in the Shade
The most obvious and effective way to prevent UV fading is keeping your car out of the sun whenever possible. Park it in the garage, under a carport, or at least under a shady tree.
For the next level of protection, there now exist a number of coatings that cover and shield the car’s paint while letting the color shine through. These products come in film layers or liquid sprays that can be applied by professionals or do-it-yourself owners.
Most modern car waxes contain ingredients that provide some measure of protection from car paint damage due to the sun, and also keeps other caustic substances from touching the paint surface directly.