The topic of preservation is always of importance to formulators and finished good marketers. Formulators are aware of the necessity to adequately preserve their products in order to ensure product safety and be in compliance with the respective legislations. This task is made much more difficult when marketing requirements are added to the factors influencing the preservative choice. Demands such as global approval, soft preservation, etc. have limited the number of acceptable actives.
Increasing marketing pressure has resulted in an interest in reducing the amount of traditional preservatives in cosmetic formulations or in finding novel ways to keep cosmetic products microbiologically stable. It is now more important than ever that preservation or microbiological stability is an integral part of new formulation concepts. At an early stage of product development, formulators must consider all possible methods of enhancing the efficacy of traditional preservative actives, e.g. using chelating agents or multifunctional materials.
Ethylhexylglycerin is a synthetic representative of the 1-alkyl glycerin ethers with a high degree of purity. Substances with a similar structure occur in nature. These alkoxylipids are widely distributed in human and animal tissue. High levels of the neutral alkoxylipids are present in the liver of cartilaginous fish. Batyl alcohol and selachyl alcohol have been isolated from the non-saponifiable proportions of liver oils of sharks and rays. Chimyl alcohol has been found in the liver of the sea rat (Chimaera monstrasa). All of these are 1-alkyl glycerin ethers, namely octadecyl-, hexadecyl- and 9-octadecenyl glycerol.
Ethylhexylglycerin is the result of the systematic study of substances in the 1-alkyl glycerin ether class of compounds. It is very stable, e.g. against hydrolysis and elevated temperature, and compatible with cosmetic ingredients. It is a crystal-clear, colourless liquid with a slight characteristic odour.
Ethylhexylglycerin is globally approved for use in cosmetic products. It is commercially available under the brand name sensiva® SC 50.