Who can say to have never played, at least once, with toy cars that change colour under running tap water, depending on the temperature: one colour under hot water, another under cold?

It was a bit like having a new toy car, which often lasted longer than all the other games precisely because we never got tired of it.
The same, of course, could not be said for the mums or dads, who had to run after us all over the house, wiping up every trail of water the little wet car left behind as it sped across the floor.

Well, Japanese car manufacturer Toyota seems to be firmly intent on going down this memory lane, turning an (old?) game into an innovative reality.

How the Toyota patent works

It was only a few weeks ago, in fact, that news broke of the filing with the USPTO (United States Patent and Trademark Office) of a new Toyota patent for a paint that changes colour whenever you want and in a very short time.
Toyota technology in fact uses special pigments that are able to change colour when subjected to specific temperatures and light sources.

According to early rumours, the Japanese manufacturer could produce all its forthcoming cars in a single colour, e.g. white or another ‘neutral’ shade, leaving it up to individual customers to customise it as they wish with the shade they prefer.
To change colour, a quick pit-stop at your local workshop (provided it is equipped with the necessary technology) will suffice. The method involves the use of a colour modulator configured to irradiate the car’s special paint for a specific amount of time with light at a specific frequency. The whole process would serve to ‘mix’ the paint molecules so that they reflect a specific wavelength of light, creating different colours each time.
Light, and the resulting heat, thus become the secret ingredients in Toyota’s recipe for this ‘customisable’ paint, so much so that the process involves the use of specific temperature sensors on the car to ensure that the correct parameters are achieved for a given colour.


The project that Toyota developed aims to meet the customisation needs of its customers, who  so far only have two ways to change the colour of their car. The first, of course, is to first remove the existing paint and then apply the new colour. An extremely time-consuming as well as expensive method.
The second involves the application of a coloured film (called ‘wrap‘) applied directly onto the bodywork: this method, however, is also expensive and has the disadvantage of a reduced lifespan. All it would take is a heavy hailstorm, or even a simple scratch, to ruin the customisation in an instant.
Hence the Toyota innovation, which also responds to the recent inventions from BMW, Tesla and Mercedes, which all seem to be heading in the same direction.
The German automotive group BMW presented at 2022 CES (Consumer Electronics Show) a paint that can change colour, specifically from white to black. The following year, in 2023, it was the turn of the launch of BMW i Vision Dee, a car capable not only of changing colour but also of projecting the driver into a true sensory experience that also includes a journey through augmented and virtual reality.

In short, the technology that will allow us to change colour depending on the moment, the occasion or even the mood is now upon us. Obviously, the transition from patent to market availability is a long and insidious process, which can take years to materialise, but the direction now seems clear and defined: the future of the four-wheeler also passes through chameleon cars.