What is the pH range of alkaline waves?

• A. 6.5 to 7.5
• B. 8.0 to 9.5
• C. 5.0 to 6.5
• D. 9.5 to 11.0

Answer: (B)

Alkaline waves rely on a basic environment that is high enough to lift the hair cuticle and break disulfide bonds so the hair can be reshaped. This chemical action happens most effectively in a pH around 8.0 to 9.5. Staying within this range provides enough alkalinity for the reducing agents to penetrate the cortex and reform bonds in the new curl pattern, while avoiding excessive swelling or damage that can come from pH values much higher.

Ranges in the neutral to slightly alkaline area (around 6.5 to 7.5) aren’t alkaline enough to drive the necessary cuticle lift and bond breaking. Acidic ranges (5.0 to 6.5) don’t provide the alkalinity needed for permanent reshaping. Extremely high alkaline values (9.5 to 11.0) exist in some formulations, but standard alkaline waves are typically used within the 8.0 to 9.5 band, which is why that option is the correct one.