Evaluation of alkenones, a renewably sourced, plant‐derived wax as a structuring agent for lipsticks

Abstract

OBJECTIVE Waxes are used as structuring agents in lipsticks. There are a variety of waxes combined in a single lipstick to provide good stability, pleasant texture and good pay‐off. Due to a significant growth for natural, green and sustainable products, there is a constant search for alternatives to animal‐derived and petroleum‐derived ingredients. In this study, a green, non‐animalderived wax, namely long‐chain ketones (referred to as alkenones), sourced from marine microalgae was formulated into lipsticks and evaluated as a structuring agent. METHODS Alkenones were used as a substitute for microcrystalline wax, ozokerite and candelilla wax, typical structuring agents. In total, 384 lipsticks were formulated: L1 (control, no alkenones), L2 (alkenones as a substitute for ozokerite), L3 (alkenones as a substitute for microcrystalline wax) and L4 (alkenones as a substitute for candelilla wax). Products were tested for hardness (bending force), stiffness, firmness (needle penetration), pay‐off (using a texture analyser and a consumer panel), friction, melting point and stability for 12 weeks at 25 and 45°C. RESULTS Alkenones influenced each characteristic evaluated. In general, lipsticks with alkenones (L2‐L4) became softer and easier to bend compared to the control (L1). In terms of firmness, lipsticks were similar to the control, except for L4, which was significantly (P < 0.05) firmer. The effect on pay‐off was not consistent. L2 and L3 had higher pay‐off to skin and fabric than L1. In addition, L4 had the lowest amount transferred, but it still had the highest colour intensity on skin. Alkenones influenced friction (glide) positively; the average friction decreased for L2‐L4. The lowest friction (i.e. best glide) was shown in L4. Melting point of the lipsticks was lower when alkenones were present. Overall, L4, containing 7% of 4 alkenones in combination with microcrystalline wax, ozokerite and carnauba wax, was found to have the most desirable attributes, including ease of bending, high level of firmness, low pay‐off in terms of amount, high colour intensity on skin and low friction (i.e. better glide). Consumers preferred L4 the most overall. CONCLUSION Results of this study indicate that alkenones offer a sustainable, non‐animal and non‐petroleum‐derived choice as a structuring agent for lipsticks.

Preliminary Study of the Potential Photoprotective Effect of Organogel-Based Lipstick Formulations: Texture Analysis, Rheological, Thermal and Sensory Properties

“…Lastly, firmness of the lipsticks was also affected by the presence of LMOG molecules and especially their weak physical interactions with the oily phase in the gel network structure, as reported [41]. This mechanical property is an important parameter that can play a role in tuning pay-off, friction and softness [35]. L3 exhibited the highest firmness and values remained constant compared to all other lipsticks over 12 weeks at 25°C (Figure 2C).…”

“…Lipstick ingredients, storage temperature and storage time had a significant effect (p < 0.05) on hardness, stiffness and firmness (Figure 2). Hardness depends generally on the type and amount of waxes in the formulation [27], the oil polarity [34] and the oil:wax ratio [35]. In all lipstick formulations, the oil:wax ratio was constant for L1 and L4 formulations but lower than L2 < L3 due to the addition of white petrolatum.…”

Development and Validation of a Method for the Analysis of Zinc Oxide in Cosmetic Matrices by Flame Atomic Absorption Spectroscopy

“…The cosmetic matrices considered in this work include lipsticks, which can be thought of as waxy matrices [ 36 ], to foundations, including but not limited to water-in-oil emulsions which contain dimethicone and dimethicone-derived emulsifiers [ 37 , 38 ], and cream emulsions that include both water-in-oil and oil-in-water emulsions [ 4 ]. The diverse chemical properties of these matrices make the use of an extraction solvent necessary, as direct acid digestion might require long times for products with high lipophilic material content.…”

Lipids from Microalgae for Cosmetic Applications

“…Alkenones can be produced in many locations, therefore, their availability is not as limited as that of some other waxes. Given their waxy nature and reasonably high melting point, alkenones could represent an attractive class of natural ingredients that may find useful applications in a variety of cosmetic and personal care applications [90].…”