Chemical Texture Services and Relaxing
What this domain tests
Relaxer chemistry, strength selection, scalp protection, processing, neutralization, and curl reforming.
Core rules
- Sodium hydroxide, or lye, relaxers are high-pH and fast; no-lye relaxers use calcium hydroxide or guanidine and can be less irritating but may leave mineral buildup.
- Strength, mild, regular, or super, is chosen by hair texture, resistance, and previous chemical history, not by the desired straightness alone.
- Protect the scalp with base, avoid scratching before service, and do not overlap relaxer on previously relaxed hair.
- Neutralization lowers pH and stops processing. Use neutralizing shampoo and check with a pH indicator or color-change shampoo; incomplete neutralization causes continued breakage.
Worked example
A client with coarse, resistant, virgin hair wants a relaxer. Reasoning: coarse resistant hair needs reliable processing, but sensitive scalp suggests avoiding a stronger formula than necessary. Choose regular strength, base the scalp, apply to the mid-shaft and ends first if the manufacturer directs, then the new growth, smooth without pulling, rinse thoroughly, and neutralize until the indicator shows the correct pH. Follow with a moisturizing conditioner.
Traps
Choosing super strength for fine hair; overlapping; skipping base; neutralizing too quickly; not testing elasticity; assuming no-lye means no risk.