The preferred stabilized hydrogen peroxide of the present invention is hydrogen peroxide in a stabilized form. A stabilized form is a form in which contact with aqueous carriers and extended storage do not result in any significant deactivation, namely chemical decomposition, of the hydrogen peroxide. The stabilized hydrogen peroxide functions as the bleaching agent in the nail bleach compositions of the present invention. At very low levels, the hydrogen peroxide will have little visible effect on nail stains. At high levels, the hydrogen peroxide will be irritating or harmful to the nail and surrounding skin. Accordingly, the stabilized hydrogen peroxide is preferably present at about 0.01 to about 10 weight percent of the composition. More preferably, the stabilized hydrogen peroxide is present at about 2 to about 5 weight percent of the composition. Most preferably, the stabilized hydrogen peroxide is present at about 3.0 to about 3.5 weight percent.
When certain thickeners are used, the addition of a viscosity stabilizer to the composition may further improve the aesthetics of the finished product. Viscosity stabilizers are useful in the nail bleach compositions of the present invention, to enhance the stability of the composition over time. The viscosity stabilizers that are preferred for use in the compositions of the present invention are surfactants that can survive in contact with oxidizing agents. The viscosity stabilizers are preferably present at up to about 25 weight percent, with a weight percent of up to about 10 being more preferred. Most preferred viscosity stabilizers include sodium lauryl sulfate (which also acts as a degreaser) and Pluronic F127, a polyoxypropylene/polyoxyethylene block copolymer provided by BASF Corporation (which also acts as an anti-irritant), alone or in combination. Surfactants can also function in compositions of the present invention to reduce the surface tension of the composition, to enhance "wet out" or dispersion of the hydrogen peroxide on the nail. Accordingly, surfactants can be used in compositions of the present invention that do not contain thickeners.
|NAIL BLEACH Wt. %|
Ultra cosmetic peroxide
Deionized water 82.42
Sodium hydroxide (25% active)
Steareth-10 alkyl ether/
The preferred stable nail bleach compositions of the present invention include stabilized hydrogen peroxide, in a pH buffered cosmetically acceptable carrier. The carrier preferably is water. More preferably, the carrier is demineralized water.
The preferred nail bleach of the present invention includes a pH adjusting agent. The pH adjusting agent or pH adjuster is preferably sodium hydroxide. The pH adjusting agent preferably places the pH of the composition at about 6 to about 9. More preferably, the pH adjusting agent places the composition at a basic pH (greater than 7), and most preferably at a pH about 8.0 to about 8.5. It is believed that this preferred slight alkalinity of the nail bleach is the primary source of its ability to effectively soften cuticles. The pH adjusting agent also acts to accelerate the bleaching process. The pH adjusting component concentration, as well as water level, can be adjusted to achieve this desired pH range.