Waxes

Waxes

The word wax has two different meanings. From a chemical point of view it means an ester of a fatty acid and a fatty alcohol. Jojoba oil is therefore a liquid wax. In this Section, however, the word wax is considered from a physical point of view, and means compounds having a high melting point (approx 50—100°C).

- Natural waxes

The most important wax, and a classical component for creams, is beeswax, which is the construction material of honeycombs.

The melting point is around 61 to 66°C. Untreated beeswax is dark-yellow and is usually treated to improve the color.
Beeswax is a very good consistency regulator in creams and ointments and is also used in stick formulations. The addition of approx. 6 percent of borax, calculated on the beeswax, results in partial saponification and provides the beeswax with some emulsifying properties, This principle was used in the classic cold-cream formulations. Nowadays, European law restricts the use of borax in cosmetic products.
Two other natural waxes that are harder and therefore mainly used in stick formulations are carnauba wax (melting point approx. 85°C) and candelilla wax (melting point approx. 70°C). Both are extracted from South American plants.

- Synthetic waxes
Due to the varying qualities of the natural products, especially yearly and source variations of beeswax, synthetic substitutes are of interest. These are often mixtures of very different chemicals, and result from empirical research. An example of a beeswax replacement the mixture of glyceryl hydroxystearate (and) cetyl palmitate (and) microcrystalline wax (and) trihydroxy stearine. A single defined product with a structure close to beeswax is hydroxyoctacosanyl hydroxystearate, an ester of a C26-β-hydroxyalcohol and hydroxystearic acid. This product, which shows very similar behavior compared with beeswax, is easy to emulsify and can be used as a general Consistency regulator for cosmetic emulsions.
Another synthetic wax is synthetic spermaceti. The natural type is no longer available because it is obtained from whales, but was formerly an excellent wax compound for emulsions. Replacements are cetyl palmitate, which is the main component of the natural spermaceti or special mixtures like the cetyl esters wax NF, which comes very close to the natural product.