Some of the most common short-chain alcohols that you will find in hair care products are ethanol, SD alcohol, denatured alcohol, propanol, propyl alcohol and isopropyl alcohol - these are the ones it's best to avoid.
Joe explains, “You may be surprised to know some alcohols are, in fact, very beneficial to your hair because they have great hydrating, moisturizing and smoothing properties.” “The complex, molecular structure of different alcohols involves different carbon chains attached to the alcohol group.
Some examples are SD Alcohol 40, Ethanol or Ethyl Alchohol, Propyl Alocohol and Isopropyl. And, it's true that using these types of alcohols on the hair over and over and not properly replacing the moisture is going to cause damage. In this sense "alcohol" (these alcohols) is bad for your hair.
Bad Alcohols: Short-Chain Alcohols. It's not a good idea for Type 4 naturals to use short-chain alcohols because their purpose is to evaporate rapidly, causing the hair to become dry. For tightly coiled hair, this is especially bad because our hair needs extra moisture, not less! Alcohol denat.