MEA vs Ammonia in Hair Color

Couple of years ago I attended a Beth Minardi Colour Session. I was amazed by the information she knew and would like to share what I received from her… this will clear up any questions you might have about Hair Colour ingredient questions.


Q. What is MEA?

A. MEA is mono-ethanolamine (C2H7NO). It’s an alkaline (as opposed to acidic) reactive chemical compound that is produced by the reaction of ethylene oxide with ammonia. It exists in liquid form and has little odor.


Q. What is ammonia?

A. Ammonia (NH3) is an alkaline compound of hydrogen and oxygen that is both naturally occurring in nature and man made. It is water soluble, highly reactive, exists in both gas and liquid form, and has a strong odor.


Q. How does MEA perform in haircolor?

A. In haircolor, MEA can accomplish the first step, which is to open the hair’s cuticle. However, it is not as efficient as ammonia at penetrating to the cortex; therefore it doesn’t allow the haircolor ingredients to penetrate the hair strands as well as ammonia.


Q. How does ammonia perform in haircolor?

A. In haircolor ammonia is very efficient at opening cuticle, which allows haircolor to penetrate more efficiently into hair’s cortex.


Q. Why is MEA not as efficient as ammonia?

A. The MEA molecule has a molecular weight of 61, while the molecular weight of ammonia is 17. Therefore, MEA is 3.5 times larger than ammonia. When permanent haircolor and peroxide meet ammonia, it acts as a catalyst. This reaction is what removes natural pigment FROM the cortex and allows artificial color to deposit INSIDE the cortex. Because MEA’s reaction with peroxide is weaker and the molecule larger it is not as effective as ammonia/peroxide at lifting natural color out of the hair or depositing color into the cortex of the hair.


Q. How do various shades of MEA based permanent haircolor perform? For example; brown, blonde, red, and for gray coverage of those shades?

A. Because of its large-sized molecule, when MEA is used in permanent haircolor products the color doesn’t lighten efficiently enough to produce exceptional light blondes and vibrant reds. Also, browns and other shades don’t cover gray well or have long lasting gray coverage.


Q. How well does MEA based demi-permanent haircolor perform?

A. The use of MEA is fully justified in demi-permanent color because lightening of natural pigment isn’t needed. This type of haircolor product is designed to leave no line of demarcation and gradually fade from the hair.


Q. Is MEA “bad” for the hair?

A. MEA is not fundamentally bad for the hair. The amount of MEA used in a particular haircolor is what creates potentially negative results. The amount of MEA in haircolor varies from shade to shade. With MEA, it is not uncommon to have 6% in darker shades to 10% in the lightest blonde shades. For ammonia, the amounts range from 1.5% in the dark shades to 3.5% in the high lift shades.


Q. Is ammonia “bad” for the hair?

A. Ammonia in haircolor is not fundamentally bad for the hair. When both ammonia (catalyst) and peroxide (oxidation) are used with haircolor, tiny molecules carry dye all the way into the cortex, where they react to remove natural pigment and expand artificial pigment to a size that cannot be washed out, creating a permanent color.
Q. What is the result of a high amount of MEA in haircolor products?

A. MEA in haircolor products remain in hair even after the haircolor has been removed. In the 24 hours following the color service, the residual MEA can cause progressive darkening and dull the shade. Color companies that use MEA in permanent haircolor fight this by using a specially formulated shampoo that contains ammonia to remove residual MEA.


Q. Why doesn’t MEA based haircolor have a strong odor?

A. By its nature, MEA doesn’t have a strong odor. It is a chemical that produces gas, but it is basically odor free.


Q. Why do some haircolor companies prefer MEA over ammonia?

A. The lack of odor.


Q. Why do some haircolor companies prefer ammonia over MEA?

A. The color results of ammonia based permanent haircolor remain more predictable than MEA based haircolor, providing more longevity, vibrancy and superior gray coverage.

Something to remember… you make the call on which Colour product you will use. There are pros and cons to every type of Colour we use, just know who your Guests are and what their needs are and fulfill them.

Find out more about Beth Minardi and Joico

Have Fun Professionals… change lives one Guest at a time.



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