There has been much research done about using 40 volume developer with bleach.
This is not recommended. Here is why...
The stronger the formula, the faster the melanin in the hair shaft dissolves. This may result in damage and weakening of the hair shaft. If you use a 20 volume developer or a 30 cream developer with bleach, the slower processing time allows the bubbles made to escape the cuticle layer of the hair shaft, allowing the melanin in the cortex to be dissolved / dispersed with little or no damage to the integrity of the hair shaft.
Try experimenting with hair swatches of 20, 30 and 40 volume (and your bleach) applied to different swatches at the same time, with the same amount of heat and you will be surprised to see that 20 volume developer effectively lightens the hair with heat as the 40 volume, but with less damage.
To order EcoColors Professional Hair Colors, it is simple, register your account with your cosmetology license number, and then contact us to activate your wholesale professional account. It will be instantly activated.
