Although it is now June, I wrote this month’s “Compass” in late April just after a good friend and I had a simple at-home chemistry lesson dyeing Easter eggs with her son. As she lined up the nine cups in which to prepare nine different colored solutions, I read the mixing instructions and we considered the various dyeing options:*
a. For Ultra Vibrant Colored Eggs—add a tablet and 3 tablespoons of vinegar to a one-cup container;
b. For Traditional Colored Eggs—add a tablet and 3 tablespoons of lemon juice to a one-cup container; or
c. For Pastel Colored eggs—add a tablet and 3 tablespoons of water to a one-cup container.
We went with option A and successfully produced three dozen hard-boiled, vibrant colored eggs. In the meantime, however, we wondered how the differences in chemistries produced different colors.
Not being a chemist, I posed this question to a formulator friend who suggested that the manufacturer had probably used pH-sensitive dyes to produce different color shades since water has a pH of around 6.5−7.0; vinegar, 2.5−3.5; and lemon juice, 1.0−2.5. Of course, as any experienced egg-dyeing child can tell you, the longer you leave the egg in the dye, the bolder the color gets. This lesson is a reminder that sometimes the seemingly simplest of variables can have a great impact on the final result.
In relation, this issue of Cosmetics & Toiletries magazine features articles that suggest how the right tweaks to some fundamental variables can improve formulations. O’Lenick and Lott, for instance, discuss how solvents can impact SPF values and describe a new ester to improve sunscreen efficacy. Grace and Plonsker explore how the process of microchannel emulsification can be used to produce emulsions with smaller droplets and tighter size distributions, improving product stability.
In “A Dermatological View,” Levin and Maibach also look at pH but in respect to how it changes in skin as it matures. And speaking of mature skin, Pugliese and Draelos review the process of glycation, which can occur with aging, and how it affects basic skin functions. Finally, we present our annual Skin Care Formulary, suggesting new ingredient combinations and product concepts.
A colleague once told me that innovation is putting new eyes on old problems and I believe this issue does just that, to assist product developers in identifying simple ways to optimize formulations.