Here’s a car that can change color
An auto detailing shop in the UK has given a car a coat of paint that changes color with exposure to different temperatures.
Remember those Hotwheels toy cars that would change color when you put them under a hot water faucet? A British car detailing firm has finally done what should have been done years ago, and applied the same type of paint to a real car. A small auto-detailing shop in the UK called Auto Kandy recently took a 200hp Nissan R33 Skyline S2 and gave it the Hotwheels treatment, making it change color dramatically from bright orange to dark purple whenever it is doused in cold water. The effect is almost immediate, and can create striking patterns on the car; excellent for showing off or hiding from the cops like in the 1981 movie The Cannonball run. It probably looks really cool in the rain too.
The color changing paint, known as thermochromatic paint, is created using either liquid crystals or leuco dyes. In all likelihood, leuco dyes were used for in this case, since they are easier to work with, cheaper and have a broader range of applications. Here’s how it works: When a thermochromatic paint absorbs a certain amount of light or heat, the crystal or molecular structure of the paint begins to change so that the pigment absorbs light at different wavelengths than before. The color we see is the light reflected back from the paint, so when the absorption wavelength changes, so does the apparent color. Check out the effect yourself in the video below!