Acids
This pH range defines acids.
0-6.9
This pH range defines alkalis.
7.1-14
Salts are formed when these two substances combine.
Acids and Alkali
The natural pH of hair and skin is approximately this range.
4.5-5.5
Is shampoo typically acidic or alkaline?
acidic
What does acids do to the hair cuticle
Close or contract the hair cuticle
Alkalis are used because they do this to the cuticle.
Raise or open the cuticle
The main job of a neutralizer is to do this
stop or neutralize chemical action
This pH level is considered neutral.
7
This product is used to rebalance hair after color or relaxer.
acid balanced conditioner or treatment
Hair and skin naturally fall into this category
Acidic
Name one strong alkali used in relaxers.
sodium hydroxide or calcium hydroxide
Neutralizers are most commonly used after this service.
perm or relaxer
High pH products cause the hair to do this
Swell the hair
What type of product would you use BEFORE a chemical service?
alkaline product
Name one acid commonly found in salon products.
citric acid, lactic acid, acetic acid, or amino acids
This chemical allows permanent hair color to penetrate the cortex.
ammonia or an alkaline agent
Salts usually fall around this pH level
7
Low pH products help hair do this after chemical services.
Return the hair to normal, or close the cuticle
Why should chemical services never overlap?
risk of over processing and breakage
True or False: Acids soften the hair.
False (They strengthen/harden hair.)
Why can alkalis be dangerous if misused?
they can cause burns, damage, or overprocessing
What happens if hair is NOT properly neutralized
continued processing, damage, or breakage
Why is pH knowledge critical for client safety?
prevents damage, burns, and chemical misuse
Which is stronger on hair: a pH of 9 or a pH of 5 and why?
pH of 9 because it is more alkaline and opens the cuticle