Acid perm lotion
Acid perm lotion has been developed as a kinder alternative to the original alkaline perm lotion. Fewer bonds are broken in the cortex of the hair by acid perms and they are gentler to use on damaged hair or hair that processes very quickly (for example, porous hair).
Acid perms have activators that are added to them immediately before use. They rely on heat to open up the cuticle scales so that they can penetrate the cortex region. They generally have an acid pH of 6–7 and are made of a chemical called glycerol monothioglycollate.
Once an acid perm is mixed with its activator it only has a short life span and, consequently, any remaining lotion should be discarded. This makes pre-perm testing with acid perm lotions difficult, as you would not want to mix up a whole bottle of perm lotion to test one small piece of hair – this would not be cost effective for the salon.
Alkaline perm lotion
Alkaline perm lotion is generally stronger than acid perm lotion and comes in different strengths for different hair types. It has a pH of approximately 9.5, which opens up the cuticle scales and allows the perm lotion to enter the cortex region of the hair. The higher the pH of the perm lotion, the more damaging it is to the hair (see ‘Facts about hair and skin’, page 19). This is why alkaline perms have conditioning agents added to them and acid perms are becoming increasingly popular. The chemical ingredient in alkaline perm lotion is ammonium thioglycollate.
Exothermic perms have the benefit of producing their own heat. Once the activator has been mixed with the perm lotion, you will be able to feel the lotion getting warm as you hold the bottle. Because they are self-heating, no added heat is necessary to open the cuticle or help the perm during processing.
Exothermic perms are generally made for use on all types of hair; however, you may need to leave them for less time on porous hair – always check the manufacturer’s instructions. They can be a mixture of acid and alkaline or acid/alkaline depending on the manufacturer. The only way to check is to look at the chemical ingredients on the packaging and compare to the acid or alkaline perm chemical ingredients.
Dual action perm
These are used when perming African Caribbean hair and are more commonly used as they are kinder on the hair than single action perms. The active chemical found in most perm lotions for African Caribbean hair is ammonium thioglycollate. It is a twostep process: first, the curly hair is chemically softened using an ammonium thioglycollate cream to reduce the natural curl; secondly, a curl gel or winding lotion (a weaker solution of ammonium thioglycollate) is applied and the hair wound around perm rods and processed. This permanent treatment allows the hair to be formed into new looser curls after neutralising has taken place. Curly perms produce a tighter, more traditional curl, while a body perm will produce a softer wave or curl for a more modern finish.
Single action perm
Again, this perm uses the chemical ammonium thioglycollate, but only one application of the perm lotion is applied and remains on the hair (during smoothing and straightening and when the hair is wound around the perm rods) until processing is complete. Remember, you must always wear gloves when winding hair that has had perm lotion applied to it.
Perm and curly perm lotions come ready to use in different strengths for different hair types.
Neutralisers come in many different forms. Some are ready to use out of the bottle, some need to be mixed with warm water, some need to be foamed up in a bowl and applied with a sponge, and some neutralisers are instant. The chemical ingredient in neutralisers may be either hydrogen peroxide or sodium bromate, both of which can lighten or fade hair colour.
Most neutralisers used on African Caribbean perms usually contain sodium bromate as this has a much gentler action on the hair than hydrogen peroxide. This is why the neutralising process differs with African Caribbean hair, as the rods are left in the hair throughout the neutralising process because the gentler action takes longer to process. Sodium bromate also has less hair lightening properties than hydrogen peroxide.
Suitability of perm lotions for different hair types:
Perm lotion and hair type
Virgin hair that has not been treated with chemicals
White or greying hair, or very tight compact cuticle scales
Hair that has been treated with permanent colours
Bleached or high-lift tinted hair including highlights (perm with great care if at all)
Dry, porous hair that has a poor cuticle area (perm with great care if at all)
Curly perm lotion and hair type
Check it out
What are the active ingredients used in African Caribbean perm lotions? How do these differ from other perm lotions?
Find out about the perming products available in your salon. This will give you confidence when having to choose a perm lotion for your client’s particular hair type. Keep this information in your portfolio of evidence.
content provided by Heinemann
You should always recommend that your client has her perm before colouring treatment, as the neutraliser is likely to fade or lighten the colour.
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