Why do some UV gel colors fade?

Question: Why do some UV gel colors fade, while others don’t?

Answer: Many colorants are affected by UV since it can cause the colorant to undergo a chemical change that alters or fades its color. Some colors are more susceptible to UV than others. Those colors at the blue end of the color spectrum are generally easier to fade than those on the red end of the spectrum. Some colorants turn yellow with enough exposure to natural sunlight since it contains UV energy. The reason some colors change and others don’t, depends on their chemical structure. Colors that have a chemical structure that is more resistant to UV are less likely to change. 

How does UV cause the color to fade or shift?
Like visible light, UV is energy. That’s why its correct name is ultraviolet energy, and NOT ultraviolet light.  Why not “light”? Light is the energy we can see; if we can’t see it, then it is not light. We can’t see UV, so it’s not correct to call it “light”. UV is pure energy! When UV collides with certain chemical bonds, this energy can snip them much like a scissor cuts a thread. When this happens, the color begins to fade or shift, because the chemical structure of the colorant ingredient is slowly changing. The more of these chemical bonds that break, the greater the change will be. Since these bonds aren’t able to reconnect, the change is permanent and the color is permanently altered. This is why newspaper slowly turns yellow when exposed to sunlight or why clothing slowly fades. It is also why cosmetic colorants in general fade and shift in color. This explains why it is important not to store your products in direct sunlight and why it is helpful to protect your nails from excessive sunlight exposure when outdoors.