Phytosphingosine for Skin Differentiation and Other Topics: Literature Findings

By: Charles Fox, Independent Consultant

Posted: December 1, 2009, from the December 2009 issue of Cosmetics & Toiletries.

page 6 of 8

The new resin wax was easily incorporated into personal care formulations based on w/o and o/w systems and showed improved compatibility with standard ingredients over conventional silicone waxes, including dual compatibility with both volatile silicone oils and organic oils such as castor oil. When used in skin creams, the resin wax acted as a rheology and texture modifier. In solid and liquid lip color and blushes the resin wax improved non-transfer properties and color intensity. Additional benefits such as improved eyelash coating and curve-holding were found with use of the resin wax in a mascara.

Renewable propanediol: Managi et al. reviewed the moisturizing characteristics and cosmetic applications of renewably sourced propanediol for skin and hair care.¹⁵ Glycols are key ingredients used in cosmetics as solvents, moisturizing agents and formulation-adjustment agents; however, most glycols are petroleum-based. With the growing trend among cosmetic customers for safe and naturally derived ingredients, petroleum-free glycols are in high demand.

In the decribed research, 1,3-propanediol, a transparent, bio-sourced glycol from corn sugar, is introduced.^b The material is renewably sourced and ECOCERT certified for the personal care market. Patch testing showed the ingredient does not stimulate the skin, and it is safe for cosmetic use. In addition, 1,3-propanediol imparts longer-lasting moisturization on skin than 1,3-butylene glycol and propylene glycol, and can be applied with glycerin to maintain the effect longer.

In hair care, 1,3-propanediol increases water content in hair and imparts moisture to hair via shampoos and leave-in products. According to the authors, renewably sourced propanediol is expected to apply to various formulations since it satisfies a natural need.

Starch-based thickening agents: Lehmann et al. have published on starch-based thickening agents for personal care and surfactant systems.¹⁶ The described work was aimed at synthesizing and characterizing a starch-based thickener for use in nonionic C14-C18 alkyl polyglycosides (APG). A new starch derivative was applied in an aqueous formula of 14% w/w APG with 0.5–2% w/w of different 2-hydroxyalkyl carboxymethyl starches as thickeners to obtain a formula registering a shear viscosity of approximately 6,000 mPas.