For as long as most drivers can remember, round and black tyres have very much been the norm. Of course, car tyres have always been round in shape, but why do we use a black tyre?
Here we will look at why tyres are this colour and what the best tyre black properties are. In case you’ve ever wondered why, we have all the answers!
What makes a tyre black?
The tyre black colour comes from a pigment used in the tyre construction, known as carbon black. This is not added as a specific coloring agent, but rather to improve the properties of vulcanised rubber. Specifically, carbon black improves the rubbers resistance to wear, increasing its lifespan and durability.
There are, of course, other benefits to using carbon black. Because the compound reduces the chances of deformation, the tyre retains its intended shape better, leading to less friction and rolling resistance as a result. It also has additional damping characteristics, which help ensure less shock is transferred to the car, improving suspension and driving comfort.
Carbon black is the ingredient responsible for black tyres.
Similarly, carbon black is also an excellent heat conductor, allowing tyres to move heat away from the contact patch, balancing the overall temperature across the tyre. Again, this helps keep deformation down and ensure a smoother driving experience.
While it has no influence on the physical properties of the tyre, it might also be worth considering the aesthetic of car tyres. The tyre black colour, as well as the matching tyre wall black, help ensure this colour matches the wide variety of colours that cars now come in. Otherwise, manufacturers would have to produce different colours for each product to ensure a complimentary look. Many drivers may also argue that black tyres do not look so bad when they are dirty, compared to white alternatives.
Were black tyres always used?
Historically speaking, the first car tyres were white. This was due to the lack of carbon black, or other black tyre paint. Instead, these early products used the off-white colour of natural rubber.
However, pure rubber, especially after vulcanisation, often tends to be soft and, as a result, is not very resistant to wear. It also heats up rather quickly, increasing the likelihood of deformities. Additional substances have been added to the rubber to help improve the tyre’s ability to cope with these temperatures. One of the original compounds used was zinc oxide, which had a distinctive bright white colour. Just as carbon black makes the tyre black zinc oxide ensured the earliest products were white.
The earliest vehicles used white tyres, without any carbon black filler
This changed around the time of the First World War, when carbon black started becoming mass produced and appreciated for its harder wear resistance and ability to disperse heat. Originally, this was only applied to the actual tyre tread itself, leaving the sidewall white. This was used throughout the following periods, which is why classic vintage tyres have a distinctive white sidewall - this still used zinc oxide.
Over time, carbon black came to be used on all parts of the tyre, leading to tyres that are completely black. Today, this is used in virtually all popular commercial tyres, including run-flat tyres, which is what today’s drivers are more familiar with.
Are other tyre colours available?
Of course, other coloured tyres can be found as various after-market or novelty parts, but there is seldom any benefit to them, aside from the pure aesthetic. Such tyres are dyed or painted after the construction process during which carbon black is used anyway. If black was supposed to be just tyre paint and was never used in the compound, the rubber would easily wear off - it’s crucial to use carbon black for a longer-wearing product regardless of other colours you might want to have.
Different manufacturers use different coloured bands
Also, when it comes to colours, you’re likely to see coloured bands on the outside of a tyre. It’s a matter of opinion whether they add some aesthetic value to the overall look, but if you think they don’t, there is hardly any other way you might benefit from them. They actually don’t matter for an average user. Coloured bands are colour-coded only for manufacturers and hence bring no practical value for users, contrary to other tyre markings that provide way more useful information.