I always assumed that the Clarisonic cleansing brush was an attempt to clean the skin via sonic cavitation, which is when sound waves cause tiny jets of water to smash into a surface to clean it, like a thousand tiny power hoses (that’s how sonic jewellery/glasses cleaners work). But for sonic cleaning via cavitation to work, you need a hard surface, which glasses and jewellery are, but skin is not, so I was pretty confused.
I recently stumbled upon a paper from 2006 in the Journal of Cosmetic Dermatology, where the inventors of the Clarisonic discuss how it’s designed to work. (Important note: the paper doesn’t present any data of the Clarisonic in action to show that that’s how it actually works, but it’s interesting to see the theoretical background anyway!)
The Clarisonic Brush Head
The Clarisonic brush head has two parts: an outer ring that’s fixed and doesn’t move, and an inner section that’s attached to a motor inside the handle.
From the Clarisonic patents, the inner section rotates back and forth between 8 and 26°, at a frequency of 176 Hz (i.e. it makes 176 cycles from the left to the right and back again in a second; you can also think of it as 352 “sweeps”).
How the Clarisonic Brush Head Works
Here’s the question: if you put the brush against your skin, which part of your skin gets cleaned the most? If you’re a normal sensible person who hasn’t looked at the Clarisonic website in much detail, you’d say, “the part of your skin that’s sitting under the moving inner portion.”
This is where it gets really interesting – the part of the skin that the brush is designed to deeply clean is actually the part with no bristles on it! It’s the skinny ring in between the outer and inner portions (0.05-0.125 inches, or 1.3-3.2 mm according to the patents).
