Ester Quats for Sustainable Hair Conditioning

By Arnoldo Fonseca

Alkyl quats, such as centrimonium chloride (CTAC) or behentrimonium chloride (BTAC), are traditional workhorse ingredients for hair conditioning. They often serve as performance benchmarks that consumers have grown accustomed to, even if consumers are unfamiliar with these components in their hair products. According to Mintel, over the last four years, an average of over 4,700 new beauty products were launched per year using CTAC and over 3,700 using BTAC, placing these among the top quats used⁽¹⁾. In hair conditioning specifically, these two quats were found in over 65% of new conditioner launches tracked by Mintel over the past five years⁽²⁾.

Nonetheless, brands have been gradually diversifying away from these materials in new product launches over the last few years, as increased sustainability awareness by consumers and bloggers have raised concerns about this chemistry. COVID-19 is accelerating this trend by engendering greater action by consumers with regard to sustainable purchasing decisions. Perhaps more acutely, COVID-19 has also exacerbated supply difficulties which are presently challenging the availability and cost-value proposition of some traditional alkyl quats. We are at an inflection point -- shifting consumer interest and material constraints are motivating a reconsideration of hair conditioning quat solutions.

Offsets to traditional alkyl quats, such polymeric quats like cationic quars, often face shortfalls in relative performance for hair conditioning and can have negative build-up effects on hair surface; this partly explains their lower use-rates in this application. Ester quats, on the other hand, are a class of cationic conditioning agents that can deliver comparable or better performance to CTAC and BTAC. For instance, in benchmark sensory tests conducted by a third-party test institute, Evonik’s VARISOFT® EQ 100 outperformed BTAC along various relevant measures (see Figure 1). 

In similar tests, VARISOFT® EQ 65 MB outperformed sensory characteristics of CTAC, while VARISOFT® EQ F 75 MB performs comparably. Hence, for performance, formulators have the ability to meet and possibly exceed consumer expectations for hair conditioning through ester quats. And, today’s supply challenges for alkyl quats makes ester quats a good option for brands to consider.

Besides comparable or superior performance, ester quats can provide a more clean and sustainable option for brands. In contrast, short chain monoalkylquats like CTAC present high aquatic toxicity which can be damaging for the ecosystem. Long chain monoalkylquats like BTAC are somewhat better but still have a relatively high aquatic toxicity profile, and their low water solubilities can present bioaccumulation concerns. Both CTAC and BTAC generally show poor biodegradation at pH greater than 7, which can suggest environmental concern in some contexts.

Ester quats, on the other hand, degrade even at a pH greater than 7 and present a much lower aquatic toxicity profile than alkyl quats. (see Figure 2). 

Evonik’s range of ester quats also have other favorable characteristics: they have ISO 16128 natural origin scores exceeding 0.7, some are RSPO certified mass balance, some are CFDA registered, and all are Halal and vegan. For natural-focused brands, VARISOFT® EQ 65 MB is COSMOS certified for hair care applications.   

The momentum of environmentally-minded consumers and the necessities brought on by COVID-19 supply constraints make the present an excellent time for brands to explore ester quats as viable options for hair conditioning projects.  Want to learn more?  Visit our intoBeauty customer portal or contact us for more information.

_{¹Mintel GNPD. Search on Quaternary Ammonium ingredient type within all Global Beauty & Personal Care during 2017-2021.}

²_{Mintel GNPD. Search on Quaternary Ammonium ingredient type within Hair Conditioner sub-category during 2017-2021.}