The Hysteresis Effect

“Remember those TV ads in which a razor traversed the skin of a man’s cheek, twin blades the size of aircraft propellers hacking into hairs giant as flax leaves?”

This is the opening sentence in an article out of New Zealand that goes into Gillette’s science of multi-blade cartridge razors. They’ve put a lot of money into perfecting the gap between blades, minimizing the distance between them while preserving ‘rinsiblility’.

The hysteresis effect is a phenomenon that the big brains at Gillette found applied to whiskers during shaving. I presume they mean ‘elastic’ hysteresis. I’m an idiot and can barely understand what Wikipedia is trying to tell me here; but I think the gist is that the whisker remains above the skin level just after it’s been shaved, because it’s been stretched a bit. This makes sense when applied to multi-blade cartridges… particularly what I’ll call ‘the ingrown effect’.

The first blade ‘pulls’ the whisker, the second cuts it below where the skin line will be, and voila! An ingrown hair!

DE wetshavers, of course, will hit that protrusion on a subsequent pass. So, maybe, the whisker has a chance to settle a bit before it’s shaved again, and ingrowns are minimized.

Or not. My science education was sorely lacking. That’s why I went to business school.