Q: What is the difference between emulsion bleach and powder bleach? Will both products give the same result? Is one more harmful than the other?
A: The primary difference between emulsion bleach and powder bleach is the particular techniques they are better suited to perform. Powder bleaches almost universally require an oxidizing developer and can be
adjusted – depending on the developer used – to create varying strengths of bleaching mixture. As expected, stronger bleach formulas lighten the hair faster and lighter, and must be used very carefully. Powder
bleach mixtures are NOT safe for use in techniques where the bleach is allowed to sit in contact with the skin.
Emulsion bleaches are often pre-mixed bleach preparations and are used often for things like lightening facial hair, and gentle lightening of the hair in other areas. These
bleaches are usually formulated to be safe for use on the skin, though it should be noted that even these can cause burns in sensitive individuals or if allowed to stay in place for too long, can cause serious
damage to the hair.
In either case, emulsion bleaches and powder bleaches stay active as long as they are moist. Furthermore, heat can speed the processing of both bleach types and can make the
emulsion bleaches more irritating to skin. So use caution in all cases.