Hair developer level refers to its oxidizing potential. The majority of hair color formulas work with a volume developer at level 10, 20, 30 or 40.
The 10 volume developer is a standard oxidizing level for permanent, no-lift hair color. It's designed for use when you want to add a color tone or tint to the hair of the same lightness level. It also opens the hair cuticle layer, allowing the color molecules to penetrate and deposit in the cortex.
The 20 volume developer opens the hair cuticle but unlike 10 volume, it provides lifting of the hair by one to two levels. For instance, if you have more than 50% gray hair, 20 volume developer is the only developer to use for 100% gray coverage and a long-lasting color.
The 30 volume developer also works like 20 volume, but it will lighten the hair's original color by two to three and is more efficient when the desired color is no more than two levels lighter than the original color. Choose a 30 volume developer when you want a developer that is stronger for a lighter and deeper color.
The 40 volume developer is the strongest and has the potential to produce significant changes. It will lift your hair four shades and is suitable for blondes, especially high-lift colors. You can use 40 volume developer when you want to achieve a medium to dark blonde. You can also use it with bleach for better results. However, use it carefully to avoid adverse effects that may arise due to its strength.
WARINING
It contains hydrogen peroxide. Avoid contact with eyes. In case of accidental contact with eyes,rinse out immediately with plenty of water and seek medical advice.Wear disposable gloves.Keep out of reach of children.Do not expose to sun’s rays.Store in a cool place.FOR PROFESSIONAL USE.
