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Currently, most single-step long-wear lipsticks have a matte finish simply due to formulation components, but fashion and beauty trends may result in the consumer desiring other options for lipstick appearance; for example, some view glossy lips as an indication of health or youthfulness. During the formulation process, the level of gloss can be measured using a glossmeter, which measures the reflection from a surface by shooting a beam of light (the incident light) at a specified angle. The reflected light is then measured and the ratio of reflected light to incident light is taken as a measure of gloss.

In using this meter, the formulation is spread between fifty to five hundred micrometers in thickness on either a Leneta contrast card or BYK Opacity Chart and left to dry for twenty-four hours at room temperature [4]. Once dry, the sample is measured at 60° on a white background using a BYK Gardner glossmeter [4]. This measurement is conducted three times and averaged. In the event that the measured value obtained at 60° is too large, therefore meaning the sample is very glossy, the angle is adjusted to 20° in order to allow for an accurate reading. This analysis can also be completed after the application of olive oil or saliva to determine the impact on formulation appearance.

Figure 1.9 Comparison of 3 lipsticks demonstrating high formulation transfer (A) and low formulation transfer (C). Each panelist kissed the white paper four consecutive times without reapplication, as seen through prints 1-4 [58].