Premium Beauty News - Initially what goal did you have in mind?
Dominique Bouvier - In fact, the aim was nothing more and nothing less than to develop an antimicrobial surface treatment on a mascara brush to ensure a better preservation of preparations during their periods of use and storage, to increase the shelf-life of mascara and reduce or eliminate the percentage of preservatives. This project was developed in collaboration with two complementary businesses, the IFTH (French Institute for Textile and Clothing) and a French manufacturer of mascara brushes.
Premium Beauty News - What process did you use and what was its principle?
Dominique Bouvier - It was of course the subject of a patent and of a registered name, Purcilon®. The development of this product needed to integrate, not only the characteristics of the formula, but also the ones of the formula’s container and/or applicator. We know that the formula and container are inseparable to preserve the intrinsic qualities of a mascara and guarantee the product’s safe use under normal and foreseeable conditions of use.
Without going into the nitty-gritty chemical details of the system, let’s say that the principle consists in depositing on the fibres of the mascara brush an insoluble salt composed of a broad spectrum preservative used as a cleaning solution for eye lenses with a good thermal stability and a large size sodium salt. The brush is then dipped in the cation/anion mixture. The brush is rinsed and dried going through a rotary drying system. To obtain a uniform and as homogeneous as possible deposit, several protocols were developed by varying the speed of reaction of reagents, the stirring rate, the drying time. The homogeneity of the deposit was of course monitored through scanning electron microscope (SEM). The nature of the fibres of a mascara brush and their shape has also been screened to identify which quality enabled an optimum adhesion of the treatment and with no release in the formula. The most appropriate fibre was found to be the smooth polyamide fibre (6.12 PA).
In the end we observed that the insoluble salt bind to the filaments and that it was stable, did not disintegrate in contact with water, or in contact with the O/W mascara formula. Of course, we defined and objectified, through a series of microbiological studies the ideal quantity of treatment. We developed a specific protocol to demonstrate in a relevant way, the effects of this antiseptic treatment, on the germs usually used in the so-called “challenge test”.
Premium Beauty News - Conclusions?
Dominique Bouvier - It is clear that this Purcilon® surface treatment opens new opportunities in mascara preservation, not only because it improves the preservation of the product after opening but because it also limits the concentration and the number of preservatives used in mascaras, thus reducing ocular intolerance. Moreover, it enables to offer wider ranges of shades, without increasing the preservative rate in the formula, some rich pigments are impacted by that, being themselves nourishing substrates for microorganisms; or to safely add nourishing actives in eyelash treatments for a use far removed from the first opening date.