Make the reaction take place quickly and efficienctly
Needed to reach the desired pH range (11.5-12.5) to
make hair swell
Calcium hydroxide has been the most choice
6. Additives
For moisturizing effect e.g. jojoba oil, Na PCA, sweet
almond oil, lanolin, shea butter, vitamin E (0.5-1.0%)
For capability to decrease inter- , intra-chain bond e.g.
urea, thiourea, guanidine carbonate