Natural wax: a problem solver in lipstick

Today, lipstick is in a high-tech sleeve and is an indispensable cosmetic accessory for billions of women worldwide. The basic ingredients are still oils, waxes and pigments as well as emulsifiers and other additives. Lipstick has to perform a difficult balancing act each day: it has to readily confer colour and shine on contact, and it has to protect and moisturise – at the same time, however, it also has to retain its shape, ideally for years. The primary stabilising component in lipstick is wax. With a melting point in lipstick between 65°C and 80°C, wax ensures that lipsticks will remain solid until skin contact and frictional heat cause them to melt. The more wax the lipstick contains, the longer it will last. In addition to lending stability, however, waxes such as beeswax also act as mild emulsifiers that promote pigment adhesion – they also enhance lipstick shine. The waxes most frequently used by cosmetics manufacturers are carnauba wax, candelilla wax and beeswax, with berry wax offering a vegan alternative. The type of wax used for a lipstick depends on its demand and on its functionality. Adding candelilla wax to a formulation leads in lipsticks to a comfortable pay off and spread well. Manufacturers use beeswax in their formulations so that pigments can be worked in more readily. Because it is sticky, beeswax also improves how well lipstick adheres to the lips, giving consumers the ‘long-lasting effect’ they are looking for. Yet depending on the type of waxes used, the amount of wax and the proportion of wax to other ingredients, problems may arise, either during the production process or in the finished product. Unfavourable climate conditions can cause lipsticks to seep oil, soften or break, while other lipstick components produce an unattractive white film. As one of the leading producers of natural waxes, KahlWax helps individual cosmetics manufacturers solve these problems using the company’s own experimental data and formulations for various application technologies.

Oil and wax incompatibility: insufficient oil-binding capacity

Among the more frequent problems that arise is a lipstick’s failure to adequately bind oil, an issue that most often occurs at elevated temperatures, such as those during the peak summer months or in tropical locations. When this happens, the lipstick seeps oil, and small oily drops form on its surface. While the oil-binding capacity is often poor when the oil-to-wax ratio is unbalanced, it can also be compromised by the use of incompatible oils and waxes. In the worst-case scenario, the signs of incompatibility may be delayed, with lipsticks only seeping oil after they are at the point of sale or in the consumer’s home. This is why KahlWax recommends that cosmetics manufacturers use natural waxes with higher melting points, such as carnauba wax – preferably a peroxide-free grade, such as KahlWax 2442L – or a peroxide-free grade of candelilla wax, such as KahlWax 2039L. Carnauba wax, which is obtained from the leaves of a Brazilian palm tree (Copernicia cerifera), is one of the hardest known natural waxes. With a steeply rising melting curve and a melting point of approximately 84°C, highly crystalline carnauba wax does an excellent job of binding both ester oils and petroleum-based oils, while also generating smooth, glossy surfaces. Euphorbia cerifera, a shrub that grows wild in Mexico, is the source of candelilla wax, which melts at approximately 72°C, i.e., at a point between that of beeswax and carnauba wax. Thanks to both its high resin content and its waxes and esters, candelilla wax has an outstanding binding capacity for ester oils – and also produces a glossy shine. The oil-binding capacity of sunflower wax (6607L), which melts at 80°C, and that of organic carnauba wax (6642) are likewise ideal, with both waxes enhancing lipstick shine.