Drool-Worthy Paints

Science promises car paint that will heal scratches, reflect some of the sun's heat and even change color in the presence of heat or electricity.

Paint has never been a simple product to make (or maintain) and it's only getting more complex. We're talking about — though not always able to buy — paints that are molecularly blended, optically deceiving and electrically powered.

Most of these changes are happening because car owners want a beautiful finish that lasts longer, but other innovations are happening because science is catching up with our feverish imaginations.

If engineers did nothing more than create paint that is both vibrant and fade-resistant, they'd be heroes to legions of car owners. It appears they might be on the verge of grabbing that crown.

For the most part, you can get vibrant colors from dye-based paints, but those colors fade. Or you can get a pigment-based coat that fades extremely slowly, but come in less-exciting hues, says Michael Venturini, marketing manager for coating at SunChemical. A type of material called nanopigments could create paints that are both bold and long-lasting.

Nanopigments, already used in paints and cosmetics, are microscopic particles that absorb and reflect light in novel ways. Venturini singled out synthetic mica, called platy alumina, as one such material that creates particularly intense, colorfast paints.

Pigment giant BASF sells nanopigments, such as its Paliogen Black, that display "solar management" traits, according to the firm. That is, they help even black paints reflect ultraviolet energy, keeping car interiors cooler than those without the pigments.

Nanopigment researchers at the Royal Melbourne (Australia) Institute of Technology say they've combined color richness, colorfast and heat-bouncing traits in nanopigments.

Most nouns following "nano" often can be dismissed as just a nice thought, but this might actually see and withstand daylight.

Of course, an eye-grabbing finish is wasted if it's marred by scratches, so engineers continue to work on self-healing paints. "Work on" is the key phrase here. While promising commercial developments have occurred over several years, there has been little significant advancement.

Nissan quietly deployed one kind of self-healing paint coating on its 2008 Infiniti EX35. (Later, it even more quietly withdrew it from North America because Nissan said the feature wasn't cost-effective in that market.) In fact, it's unclear whether any of Nissan's competitors, or even independent paint shops, carries the paint.

There are two healing methods today. Nissan's paint contains tiny elastic bubbles of a clear liquid. Scratch the paint lightly and the liquid flows into the resulting crack, not unlike an invisible scab.

A newer method involves either oxetane molecules or chitosan, a material similar to that found in lobster and crab shells. Small scratches are repaired in about an hour as sunlight prompts the healing material to reach across the scratch, like sutures, and pull the two sides together.

The devil is in the detailing (apologies). To be self-healed, the scratches have to be fine as hair with both methods — scuffs at most. Each bubble can heal just once, while the lobster-shell stuff reportedly never tires of healing scratches. Of course, no one knows how long the repairs will hold because both methods are so new.

Self-healing paint seems physically possible, if not financially viable. That said, making something that's complex even more so generally ends in unpredictable results.

On the truly exotic front:

  • There are those who swear Nissan is working on a polymer embedded with iron oxide that will change color when it's shot through with an electric current. Nissan, however, is mum on the idea. A similar technology is used on the side of some small batteries to show how fresh they are.
  • Finally, there's thermochromic pigment, which changes color as it cools. So, if you return to your white car in the mall lot and it's black, beware the black leather seats.
© Cars.com 04/30/2012