Modifying the exterior of your car is a big commitment. Either you’re applying new paint, which is a pretty permanent change, or you’re installing stickers or a wrap, which takes time, money, and effort. If you end up not liking the finished product, you can’t just flip a switch and turn your car back to how it was before, or get a refund.
That is, unless you have a Porsche with this new color-changing exterior film. The German luxury car maker recently submitted a patent application to the World Intellectual Property Organization (WIPO), describing a material installed on the exterior panel of a car that, when an electronic voltage is applied, changes colors.
Porsche, being the maker of the iconic 911, decided it would be best to use this technology as a way to incorporate racing stripes on demand. The patent application describes the film as changing colors to make racing stripes appear on the hood, roof, and rear decklid when the car is placed into a different drive mode. But Porsche also says it can be used as a way to display an EV’s state of charge, allowing drivers to simply glance at the car’s exterior to see whether it’s charged up enough to drive.
The patent application describes this film as “electronic paper” or “paramagnetic coatings,” which can alter their appearance based on how many volts are running through them. From the description:
[T]here are so-called “paramagnetic coatings” that change color when an electrical voltage is applied. Also known from the prior art are so-called e-papers (electronic papers) that allow their appearance, such as color or contrast, to be altered by applying an electrical voltage. E-papers, for example, in the form of a film, can comprise a multitude of microcapsules containing particles of one type and particles of a second type. The particles of the first type can differ from those of the second type in color and charge. Applying an electrical voltage alters the arrangement of the particles within the microcapsule, thereby causing a color or contrast change.
This tech isn’t exactly new. Companies like Porsche, Audi, McLaren, and Mercedes-Benz use a similar type of coating in sunroofs to adjust the amount of sunlight coming through the glass. In Porsches, this feature is called “Variable Light Control.” Here’s a video of it working:
Where this patent application differs is in how the film is used. Instead of on glass, the electronically charged film is placed on body panels, and, in the case of Porsche’s example, patterned to show a set of racing stripes running down the center line of the car’s exterior.
In normal driving mode, these stripes are invisible. But when the drive mode is switched, they appear out of thin air. Porsche describes the stripes as “rally stripes,” and also predicts the film could be used to distinguish cars in a race, which feels a bit more practical than someone trying to trick people into thinking they own multiple Porsches. From the patent app:
[T]he control unit is configured to control the optically variable coating in the second driving mode such that one or more color-contrasting stripes running parallel to the longitudinal axis of the vehicle are formed. Such a design, namely color-contrasting stripes running parallel to the longitudinal axis of the vehicle, is colloquially known as rally stripes. Such rally stripes are used particularly on sports cars when the vehicle participates in a race. The color-contrasting stripes serve not only to visually enhance the vehicle but also to distinguish the different vehicles participating in the race. This is particularly advantageous when several vehicles of the same type or with the same exterior design are participating in the race. This makes recognition and differentiation easier for both spectators and pit crews.
In the case of a road car, the stripes aren’t the only thing that would appear. In an additional drawing, Porsche describes how the sideblade panels behind the rear wheels and the diffuser area could also change color when placed into sport mode, highlighting the car’s sportiest elements to the public.
Adding or deleting fancy stripes from your Carrera Cup car isn’t the only way Porsche proposes this film could be used on the exterior body panels. The company also positions it as an external display of the car’s current state of charge.
Basically, the film would use a computer to signal how much charge the car’s battery has, and display that on a piece of body panel, “such that the color of the coating depends on the current state of charge,” according to the patent application. So, for example, if the film is showing red, that means the battery isn’t charged. But if it’s showing green, that means the car is charged up and ready to drive. And if it’s showing yellow, it’s somewhere in the middle.
While this all sounds like pretty advanced, expensive tech, Porsche points out in the patent application that it’s not too far from reality:
It is considered particularly advantageous to modify the optical appearance of the coating using electrophoresis. The advantage lies in the relatively low energy consumption required to change the color. Furthermore, when modifying the optical appearance via electrophoresis, especially the change in the outer color, it is possible to design the modification in such a way that electrical energy is required to effect a change in the state of the outer color, but no electrical energy, or only a significantly lower amount, is required to maintain the existing state.
Of course, there’s no telling whether color-changing film will ever make it to a Porsche production car, or even a Porsche race car. Many pieces of tech found in patent applications never see the light of day. In this case, though, it seems there are at least a few practical reasons for this to actually exist in the real world. What would you use this color-changing film for? Let me know in the comments, I’m curious to hear what you think.
Top graphic image: Porsche
The whole car. Evading persuit. Over license plates. Evading cameras. It has use cases, they just aren’t…. good for society.
Not just those bougie companies; we had a Renault Espace rental and it had this as well. It’s very “ooohh, aaahh” when you use it the first couple times, then you start wishing for a retractable cover instead.
This is exactly the opposite of what it should be. When the car is in Sport+ I want the exterior to be as sleeper as possible, not shouting “I’m in high performance mode!”.
That’s like cars that have a spoiler that deploys at 70 mph and stays deployed until you turn the ignition off. I think Porsche was one of the firsts. Anyway, one of the first mods that came out was a switch that would make it deploy as soon as the ignition was on, so that it didn’t serve as evidence of speeding.
A practical application of this is ‘unmarked’ police cars. No more wondering if you’re being pulled over by real cops, or some yahoo with Temu reds and blues. Flip a switch and the unmarked unit is now fully marked.
Can I put these “Stripes” on my EM-50 Urban Assault Vehicle?! Ha ha
Oh, so now people can buy a gray car that turns into another shade of gray.
To be fair, Porsche do have some great colours available, if only buyers pick them. (I saw a 911 in a lovely dark metallic green the other day)
I like it. I don’t know about the practical applications for it (charging indicators are already kind of a solved problem thanks to cheap and plentiful LEDs, so unless this can be done even cheaper it seems like a bad use), but I love the idea of having some 90s-style graphics on my car for fun days, but being able to turn them off when I’m going somewhere more serious.
As the guy who just put racing stripes on a Buick, I welcome this development.
Please let it be a Rendezvous.
A zebra may not be able to change it’s stripes, but maybe a Porsche can.
One word:
CannonballRun2
Can the stripes change color? Otherwise I’m not sure how much benefit it is for a bunch of Porsches on the track where half of them have the same stripes.
Finally, a way to display text on your trunk – you know, to critique the other guy’s road manners…
I don’t want to be pedantic but since it’s my line of work…
If it’s just an application, the title is technically misleading as it’s not yet granted – so they haven’t actually patented this yet.
Also, can you provide a link to the patent application? I didn’t see one and it would be neat to be able to check it out further.
“patent pending”
I can think of better ways to utilize this technology.
(Someone cuts me off in traffic. Suddenly, my car’s hood sports a giant middle finger….)
Agreed, but I prefer a thumbs-down. For some reason it really hurts people’s feelings more
I usually give bad drivers a thumbs-up, nod, and mouth “good job”.
Ranks up there with blowing kisses when someone flips you off! The unexpected response causes their brain to sieze for a second trying to grasp what you did instead of the expected angry response.
I go for the head-shake and disappointed look, in a “come on, you can do better than that” kind of way.
One step closer to our Amon Tobin future: https://www.youtube.com/watch?v=HsdBgQqBfsM
I hope they offer custom Pattern to Sample options so I can fulfill my lifelong dream of having Freezy Freakies livery on a 911.
In the Robot design, natch.
Pasha mode!
Using this on racing vehicles to dynamically indicate what position the car is in would be pretty neat, from a spectator point of view. Especially in longer races when it can be confusing to differentiate between the leaders and those who are getting lapped.
IMSA and WEC already use LED panels to do this, which might be one of the best improvements to the sports car racing spectator experience ever. IndyCar tried it for a while but I think they stopped a few years back.
How come no one has made a body like the old Hot Wheels “Color Shifters” cars?
You could have two completely different colors for your car depending on if it raining or not!
I’ve been wondering that for the past 40 years…
I can’t wait for a racing stripe subscription.
Rally Stripes. They’re Rally Stripes.
Don’t stop at the stripes. I want the whole paint job to change. I want James Bond ‘instant car color change’ when I’m being chased or followed by the bad buys. Having flashbacks to Cannonball Run and the Lambo getting ‘washed’.
Ah yes, Cannonball Run II with Catherine Bach and Susan Anton in the white/red Countach…
Be on the lookout for Johnny Dangerously and two accomplices in a black sedan! I repeat: in a black sedan!
Of course if they did those diffuser stripes in the back of the car, someone is going to change it to give the middle finger.
…I feel like I’d use color change film as a brake light supplement. More red more better, right?
I thought of that too, but this type of film usually has a relatively slow activation time compared to LEDs or even incandescent lights so I’m not sure how much it would help. I could see this being a supplement to hazard lights though.
“But Porsche also says it can be used as a way to display an EV’s state of charge, allowing drivers to simply glance at the car’s exterior to see whether it’s charged up enough to drive.”
But in order to activate this feature, will you have to push both ends of the strip painfully hard with your fingernails?
Can they also include a disappearing version of the little manual transmission sticker so I can decide now insufferable I want to be on any given day?
How did stripes ever become “racey” to begin with? For a street car I find them to be heinous.
I presume it was a way to differentiate your cars on a race track before we had the ability to put ridiculous graphics on cars, at least easily.
I think it was Briggs Cunningham who originated the over the body twin stripes (that we usually associate with Carroll Shelby) in the 50s as a way to provide the US international colors (blue and white) on his race cars.
Since we were one of the few countries then to have more than one color (e.g. Italy was red, UK was dark green), stripes were probably the easiest way to go.
Interesting! Thanks for the info!
For a little more detail, blue was France’s racing color and white was Germany’s. Nowadays, Germany gravitates towards silver and Japan races in white, though they’re officially white/red.
Wasn‘t Germany‘s silver from early on? At least the cars were called ‚silver arrows‘ and there was some weight saving done by not applying any color paint and showing the pure aluminum/steel underneath
Prior to the Silver Arrows, their national racing color was white, and it still technically was for a while after. Some German teams still race in white, but silver is definitely more common now.
Thank you!
Blame Briggs Cunningham. He popularized The Stripes as a stand-in for the white body over blue chassis that was the American National Racing Colors at the time, since new construction techniques meant Chassis were no longer visible. Then Shelby inverted the colors.
Interesting! Thanks for the info!
The first street cars to use racing stripes were the 1964 Renault 8 Gordini (white offset stripes over blue body) and the 1965 Ford Mustang GT350 (blue stripes over white body). On the Renault, the stripes were mandatory but they were optional on the Mustang (28% take rate). And then all of a sudden stripes were everywhere.
These were obviously inspired by the racing cars. In addition to what others have pointed out I’ll add that pre-war cars could feature a visible chassis painted a different color, which is what the U.S. did (white over blue). After WWII, endurance racing cars no longer had a visible chassis so the stripes were a handy innovation.