How hot is too hot and why?

Let's Talk About Temperature: 

Hair contains three types of molecular bonds:

  1. Salt bonds
  2. Chemical bonds (these are the bonds that are opened during chemical straightenings and "keratin treatments".
  3. Hydrogen bonds - essentially, water.

These hydrogen bonds are what we open in every hair styling process (DAFNI, blow dryer, straightener, Babyliss, etc.). And just as the boiling temperature of water is constant at 212 degrees Fahrenheit, the temperature for opening hydrogen bonds in dry hair is constant at 320 degrees Fahrenheit. **Always 320 degrees, regardless of hair type.

So, what does change? The amount of hydrogen bonds that need to be broken (like the amount of water that needs to be evaporated). In such cases, we don't increase the temperature but the power, like turning up a blow dryer to maximum RPM. DAFNI operates at 400 watts and works with a software that maintains a stable temperature, so there's no need to worry. ✅

But why 365F degrees? Because heat takes time to transfer from one body to another, so to reach 320 degrees in the hair, we need to start a bit higher. 365F degrees is the optimal temperature for heating during brushing (don't forget to brush slowly, the secret is always heating and adding tension, so that the hydrogen bonds in the hair set and cool in the new shape).

And what about damage? As you can see in the graph, above 220 degrees celsius (equivalent to 430 Fahrenheit), the keratin in the hair gets damaged - it's the main protein that builds and structures the hair and is very important :) So, don't harm it with high heat.

A final note about heat protectants (there was a separate newsletter about them - we're happy to send it to anyone who wants - just ask :))

A heat protectant for hair is always recommended, even when the heat is gentle and with very low potential for damage because it wraps around the follicle and conducts the heat better, which reduces the exposure time to heat. This is our heat protecting spray.


Hope you learned something new, we're available for questions, email us at

Sharon and the DAFNI Team 💗


**In wet hair, it's lower because the bonds are not yet set but wet hair is more stretchy, delicate, and more susceptible to damage, so it's recommended to evaporate water from the hair with low heat.


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