Using self-manufactured compounds, Gelest Inc. has developed a line of surface modifiers for pigments and fillers designed to address the color cosmetic chemist's formulation needs. There are four surface modified pigments, including Silky Slip (SS), Super Durable (SD), Hydrosperse (HS) and Maximum Loading (ML). The surface treatment processing of pigments and fillers is carried out at the company's newly constructed powder facility.
SS (INCI: Stearyl Triethoxysilane) imparts the wetting properties of the shorter chain silanes with a more emollient skin feel into powders and dispersed systems. In addition to providing a lubricious skin feel and aesthetics, the ingredients add water repellency and improved skin adhesion to formulations. The stearyl silane also enhances compressibility in pressed powders and cushion due to the treatment's melt point. Finally, the silane is said to improve wetting and dispersion capability. Recommended applications include: loose powders, pressed powders, w/s foundations, w/o foundations, powder/cream products and sunscreens.
SD (INCI: Polymethylsilsesquioxane/trimethylsiloxysilicate) improves the adhesion of pigments and fillers to skin and hair. Since SD pigments are hydrophobic yet not overly sensitive to oils such as sebum, they are particularly well-suited for use in eye makeup formulations. In addition to improving wear, skin adhesion and compressibility, SD adds water repellency and low oil absorption to mascara eye liner and pressed powder eye shadow. The company recommends SD for long wear eye cosmetics.
HS (INCI: Sodium Carboxyethylsilanetriol) creates an anionic hydrophilic reacted coating that provides dispersion in aqueous media without high shear agitation. Benefits of HS include: improved wetting in aqueous systems, dispersion in water with low shear mixing, complete color development, higher tinting strength, capability to achieve high pigment loading, and reduced tendency for color flotation and plate out. HS is recommended for liquid eye liners, mascaras, o/w foundations and water-based concealers.
Finally, the ML (Proposed INCI: Lauryl PEG-3 Dimethicone) treatment coats pigments and fillers with a combination of alkyl and polyethylene glycol functional groups that are balanced to maximize wetting in non-polar oils. ML allows for high pigment loading, pigment wetting in oils, low oil absorption, water repellency, low viscosity dispersions and improved compressibility. The ingredient is recommended for powder/cream formulations, pencils, cream eye shadows and stick eye shadows.
According to the company, it can also surface modify customer-supplied substrates utilizing in-house silane and silicone technologies. A wide range of specialty pigments and fillers can be handled, including those that require special processing conditions, such as inert atmospheres, low temperatures or vacuum drying.