For many years, cosmetics have been used to enhance features, achieve certain styles, and help individuals stand out. As early as 4000B.C. the Egyptians used kohl, a ground mineral, to darken their lashes, brows, and eyelids. Today, mascara is used to enhance eyelashes, and is now marketed for specific features such as water resistance, longevity, lengthening effects, and darkening effects. The main ingredients of mascara are wax, water, pigment, and binders. These ingredients make up the two phases in mascara production; an oil-soluble and water-soluble phase. The oil-soluble phase contains waxes, vitamins, and a water-resistant chemical. The mixture is heated until the wax melts and the ingredients are mixed. The water-soluble phase is prepared separately. This is made from water, an emulsifier, and pigments for colour. This is then mixed while adding a pH buffer and other chemicals. Once both phases are prepared, the two are mixed until combined.

It is important for the finished mascara to be stable enough to prevent microbial growth, but not harsh on the user’s eyes. The final product is measured in a quality control lab for viscosity and pH. Eyes have a pH of about 7.0, so it is important that the final product is pH-balanced, so it will not cause eye irritation. The ideal pH of mascara is between 6.5 and 8.0.

Application:

A cosmetic manufacturer was interested in adding a pH meter and probe to their quality control lab for their mascara line. They were not happy with the general-purpose pH bulb they used for other products and wanted a faster, more accurate way of monitoring their mascara. Hanna recommended the HI5222 Laboratory Benchtop pH meter, with two-channel capabilities and the FC240B pH electrode with stainless steel body.