Shin-Etsu Silicones has premiered its anhydrous silicone emulsion system with 10% L-ascorbic acid said to overcome key Vitamin C stability issues.
Due to its effectiveness at improving the skin’s overall appearance by reducing the visibility of pigmentation caused from inflammation, as well as increasing collagen that improves skin firmness and elasticity, Vitamin C is one of the most popular ingredients on the market.
However, the downside of working with ascorbic acid is that it starts to degrade and oxidize in the presence of water, oxygen, and light−where much of actives' efficacy is lost within a short period of time.
For formulators, this presents a multitude of challenges and limitations in water-based serums, lotions, and creams in its usage.
To propel this trend in Vitamin C cosmetics applications forward while improving stability and sensorial benefits, Shin-Etsu Silicones of America (SESA) introduced its Shin-Etsu Formulation Design 10% anhydrous silicone serum system at The Society of Cosmetic Chemists (SCC) 76th Annual Scientific Meeting & Showcase in Los Angeles in mid-December.
The Formulation CAL16-60 system is said to stabilize 10% ascorbic acid in a non-aqueous emulsion (polyol in oil) with desirable sensorial aesthetic benefits.
Formulation CAL16-60 combines three key ingredients to create great sensory feeling in a 10% Vitamin C serum which is stable−with no oil separation, even at elevated temperatures.
With over two years of research and over 70 test trials, SESA discovered their unique polyglycerin modified cross-linked and alkyl branched emulsifiers created a stable formula with superior sensorial effects.
The KF-6105 is the main emulsifier and most critical in providing stability in emulsifying.
The KSG-710 is the co-emulsifier and significantly improved the formula’s stability with a lighter skin feel.
The aesthetics of the formula were further enhanced by incorporating a lighter feeling elastomer gel in a volatile diluent−USG-1010.
The newest ingredient in the formulation, the USG-1010 helped Shin-Etsu get over the hump of the sensory challenges and further stabilized the system.
The final formulation is an opaque lotion that has a non-greasy, velvety texture that absorbs quickly with a powdery non-tacky after-feel.
“It’s challenging to create a stable system with superior sensory effects in Vitamin C,” said SESA cosmetics application laboratory team leader Janine Cherette.
“This is SESA’s first foray into the Vitamin C arena after many years of work, and we were able to accomplish a highly unique and effective silicone formulation that achieves these essential goals,” she added.
