NIC Cosmetology Written (Theory) ExamHair Care and ServicesMedium
A client with very fine, delicate hair requests a permanent wave. The cosmetologist should select a waving solution with a lower pH and a slower processing time to minimize damage. Which type of permanent wave solution best fits this description?
- AThio-free wave
- BExothermic wave
- CAlkaline (cold) wave
- DTrue acid wave
Show answer & explanationAnswer & explanation
Correct answer: D. True acid wave
True acid waves have a lower pH (4.5-7.0) and require heat to process, resulting in a slower, gentler action suitable for delicate hair. Alkaline waves are highly alkaline, exothermic waves generate their own heat, and thio-free waves use different reducing agents.
Why the other options are wrong
- A. Thio-free waves use different reducing agents but can still have a high pH, making them potentially unsuitable for delicate hair without further specification.
- B. Exothermic waves generate their own heat, but their pH can still be high, potentially too strong for delicate hair.
- C. Alkaline (cold) waves have a high pH (9.0-9.6) and process quickly, which could be too harsh for fine, delicate hair.
True Acid Wave
A permanent wave solution with a low pH (4.5-7.0) that requires external heat to process, offering a gentler action suitable for fragile or delicate hair.
- Low pH (4.5-7.0)
- Requires external heat
- Gentle processing action
- Ideal for delicate, fine, and color-treated hair
Memory trick: For 'delicate' hair, 'true acid' is the 'gentle' choice.