As seen in the July 2020 issue of Global Cosmetic Industry Magazine

The humble cosmetic stick has seen a steady increase in popularity in recent years. Initially introduced as a solution for single-function products such as eye shadows and concealers, the stick format has seen continued success as more and more brands have introduced stick variations for color applications.

Between 2015 and 2019, there was a 114% increase in new color cosmetic stick product launches. It’s no surprise that the increased popularity of stick formats has also aligned closely with the increased consumer demand for convenience and portability. A stick is an easy-to-carry solution that can be applied directly with little fuss—the perfect convenient color solution.

One product that does two or three things means having less to carry when traveling, less to learn in terms of application, and more flexibility to create a range of looks with fewer products.

If that list of requirements isn’t challenging enough, formulators also need to consider how to create a multifun­ctional stick that meets the new clean beauty demands that are impacting every segment, including color cosmetics. Clean beauty claims are the fastest growing in terms of NPD, and consumers are looking for brands that align to their principles and values.

One of the most interesting and challenging tenets of the clean beauty movement is a short INCI list. However, a glance at some typical color cosmetic stick products reveals that many have quite a long list of ingredients. This is not surprising given the performance requirements, and the sometimes-conflicting properties desired for these type of products. The right balance of texture, color, stability and wear is not a simple ask, often leading to a complex ingredient list.

When formulating color cosmetic sticks, the temptation is to put together an initial formula with all components and then add additional ingredients to fix issues or balance competing properties. Unfortun­ately, this approach can be part of what leads to those lengthy ingredient lists, keeping many sticks out of the short INCI category.

Strategies for simplified formulas

Our team has developed a different approach to cosmetic stick development featuring simple ingredient lists—without compromising on performance. The approach involves screening the individual compatibility of the structuring waxes and oil components first, before beginning to optimize the complete formula. This helps to achieve high performance with a shorter INCI list. To illustrate, we present a recent project: a clean multifun­ctional stick for lips + cheek + eyes.

Our team has developed a different approach to cosmetic stick development to help formulators create new innovative products that can claim simple ingredient lists, without compromising on performance. Our approach involves screening the individual compatibility of the structuring waxes and oil components first, before beginning to optimize the complete formula. This effective approach helps to achieve high performance, with a shorter INCI list. Let us walk you through how it works, with a project our team completed—a clean multi-functional stick for lips + cheek + eyes. Request the full Clean By Design formulation or sample here.

Emollient and structuring wax compatibility screening

In addition to clean beauty claims, we were asked to ensure the multi-stick would be extremely creamy to allow for smooth application on lips, cheeks and eyes. We also wanted a color that popped but was still buildable, so the user could create a range of looks with just the one stick.

To begin, we evaluated the compatibility of each emollient oil we planned to use with a structuring wax. For emollients, we selected Solvay’s Mackaderm® LIA because it is a high spreading, light and non-greasy ester oil made from sugar cane. We also selected INOLEX’s SustOleo™ DCS since it is a palm-free, 100% natural emollient with light cushion and silky after-feel. If we could achieve a short INCI list with these two naturally-derived emollients, we’d have an unbeatable clean formulation.

When formulating stick products, there is an optimal amount of compatibility between the oils and the structuring wax to achieve the desired smooth, creamy texture. Figure 1 shows incompatibility when evaluating an initial structuring wax at 15% with both Mackaderm® LIA and SustOleo™ DCS. The texture and feel of these blends was grainy, rather than smooth and creamy. We could improve the compatibility of this blend through a combination of lower and higher melting structuring waxes, and additional types of emollient oils, but that would defeat our goal of a simple INCI list.

Stick optimization

With the knowledge from the compatibility screening study, we developed an initial formula by adding pigments, flavor, and anti-oxidant vitamins to the Mackaderm® LIA, SustOleo™ DCS, and PERFORMACOL® 425 Alcohol.

In the initial prototype, shown in Figure 3 (left), color differences developed. They can be seen along the right edge and on the bottom where the surface is broken, indicating that the pigments are not evenly dispersed. We then looked for one ingredient that could help further optimize this initial formula. In the end, we added LexFeel® Vibrant MB, which is a USDA Certified Biobased product with 82% biobased content, and promoted as improving pay-off and vibrancy of pigments in color cosmetics, while providing a creamy texture.

When comparing the stick products in Figure 3 (right), LexFeel® Vibrant MB improved the distribution of the pigments in the stick as shown by the uniform color of the stick.