Consider, for a moment, the task of your razor. It must cut down a dense forest of coarse, stubborn hairs, and do it (ideally) in one pass. The hairs grow in every conceivable direction—including back into the skin—to dodge the blade’s advances. No matter. Each hair should be razed as close to its root as possible, but without damaging the soft, pliable surface from which it grows.

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It’s a fool’s errand, really. But there’s a way for the razor to win. First it needs to slice into the hairs with a very thin, very sharp blade, and make the cut as effortless as possible. Then it needs to ease whatever friction might occur between the skin’s surface and the metal that passes over it. The design of the razor should be able to traverse small bumps, square jaws, thin upper lips, and fleshy corners under the chin. It can be done! But it’s taken nearly the entire history of man to get it right.

Let’s just say, we’ve come a long way since removing hair with clamshells and shark’s teeth. The earliest shaving tools, described in cave drawings, employed a kind of catch and pull method, piercing the hair’s tough outer layer before forcefully breaking off the rest. Ouch. Shaving tools became more sophisticated for the Egyptians in the 4th millennium BCE, when razors made from solid gold or copper were used to liberate citizens of their unwanted manes. The face-scrapers likely evolved from flaying knives. One edge of the metal was sharpened on a crystalline whetstone, and they were handled either by gripping the blade’s blunt back edge or with a small handle attached to one side.

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Gold and copper, though, are pretty soft to be standing up to stubble. To build a better razor, we needed tougher materials—tougher materials that just weren’t available yet. It wasn’t until 2000 BCE, when humans learned to pull iron from ore, that tools became eligible for an upgrade. Shavers switched to iron around 1000 BCE. To give you a sense of how comfortable the experience was, some people preferred to pumice their face with volcanic rock as a hair-removal alternative.

The story of the modern razor really begins with King Camp Gillette and his safety razor in 1903.

Gillette was a salesman, and the straight razor really began to bother him. For one, it was hard to use on a train. And when they got dull enough, the only way to sharpen them was to take them to a barber, which was a drag, especially if your work is on the road. Sharpening the blades wouldn’t be an issue, thought Gillette, if one could only swap the blades out. It would require a complete razor redesign, of course, but Gillette was confident enough in his idea to take it on. What he came up with was a double-edged blade made of thin metal and cut from a template. The blade could be snapped into a base atop a handle. Overtop of the blade was a plate—the “safety” part of the razor—that guarded the blades from sinking into the skin. His invention was a hit, and we've made plenty of improvements since.

Image Credit: US Patent Office

Today Gillette’s blades are thinner than a surgeon’s scalpel and coated in a diamond-like carbon film with a telomer coating that ups the blade’s strength and decreases the friction over cheeks and around chins respectively. Blades are given individual suspension systems, a lubrication strip that leads the mission, and a “fin guard” that pulls back the skin to give the blade more intimate access.

It sounds like pampering compared to shark’s teeth, but there’s still a lot of pressure to innovate. Razors are a $30 billion industry worldwide, and a lot of people want in. They plan to do it with better materials.

Image credit: US Patent Office

In 2010 a German company called GFD thought they might pull a reverse-Gillette and make blades that would remain sharp for years. GFD was already in the business of super-sharp cutting tools, and they thought they might transfer their expertise to razor blades. Their creation was a tungsten carbide blade coated with a synthetic diamond film. After being sanded down by plasma, GFD’s creation was only a few atoms wide at its leading edge, so sharp that when the journalist Cyrus Farivar tested the blade three years ago, he recalled that just grazing his arm hair sliced off the hair’s tips.

And then in the fall, the University of California at Davis announced that an electrical and computer engineering professor, named Saif Islam, had come upon a promising blade by accident. Islam’s team was working on etching solar cells from silicon wafers, which involved creating tiny vertical walls emerging from the wafer’s top. The process produced some duds, but upon further inspection, Islam realized that those mistakes turned out to be breakthroughs. The misfit walls were very thin and very sharp, just a couple of atoms across at their sharpest point. Moreover, the blade’s toughness is stronger than metal, and approaching what you’d expect from a diamond blade. Mount the blades and add a handle, thought Islam, and the university experiment could be spitting out smoother faces in no time. That’s the goal, anyway. Islam’s new company Nano-Sharp is beefing up their business plan in a start-up in a university incubator at the school’s college of engineering.

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The hair, for what it’s worth, seems fairly immune to all the high-tech bullying. Its outer-layer, made of tiles of flattened cells, will continue to put up a good fight, no matter how many times it’s been severed. The hair will just grow back, forever egging us on to attack it with the sharpest, strongest, smoothest hair-hacking tool scientists can dream up.