Chemical Services
One chemistry, three services
Relaxing, permanent waving, and coloring all change bonds inside the cortex, so they share one rule: analyze first, test always, and never stack processes.
Relaxers. Sodium hydroxide (lye) products are strongly alkaline and require a protective base cream. No-lye products use guanidine or calcium hydroxide with an activator. Ammonium thioglycolate relaxers work at a lower pH. Retouch applications go on new growth only; pulling product through previously relaxed hair risks breakage. Lye relaxers are followed by an acid-balanced shampoo to lower pH and remove residue, while thio relaxers need an oxidizing neutralizer to rebuild disulfide bonds.
Permanent waves. Alkaline thio waves and acid-balanced waves differ in pH and processing behavior, but both follow wrap, process, rinse, blot, neutralize. End papers control the ends, tension controls the curl, and the neutralizer (hydrogen peroxide) fixes the new shape. Never neutralize on soaking-wet hair; the water dilutes the product.
Coloring and lightening. Levels run 1 (black) through 10 (lightest blonde). Developer strength determines lift: 10 volume deposits, 20 lifts a level or two, 30 and 40 lift more aggressively and are used off the scalp. Patch test 24 to 48 hours ahead, strand test each new client, and fill before darkening heavily lightened hair. Metallic or henna-treated hair is not lightened.
Traps to expect: relaxing and lightening in one sitting, and skipping the patch test because the client "has colored before."
Rule of thumb: one chemical process per visit, with a strand test on every new client.