Personal Care Magazine: Emulsifiers in personal care: Where do they stand?
Emulsifiers are one of the most important ingredients in the personal care and cosmetic industries. They are used to create shelf-stable products with a pleasing appearance and texture by combining immiscible water and oil-phase ingredients. Many skincare products, such as creams, lotions, serums, cleansers, sunscreens, and lip products, are available as emulsions.
Emulsifiers are also used in widely used cosmetic products such as foundation, creams, mascara, and lip products to ensure even product texture and stability. Shampoo and conditioner, which are mostly water-based emulsions, are the most prominent hair care products containing emulsifiers.
Polysorbates, lecithin and PEG derivatives are some of the leading emulsifiers in the industry. The dosage of these emulsifiers varies, but it is typically between 0.5-10%.
A product may also contain multiple emulsifiers that work together to meet the desired specifications. Emulsifiers are used in many products and for a variety of reasons, including HLB (hydrophilic–lipophilic balance) value, compatibility with other ingredients, and safety concerns.
The use of emulsifiers may also be influenced by their other functional benefits, such as emolliency, thickening, dispersion, and so on. In different sub-categories across the personal care spectrum, emulsifiers offer both main and supporting benefits for the required performance offered by the product category.
For example, in skin care, emulsifiers offer emulsification, emolliency, dispersing properties, anti-oxidation, conditioning, etc. Even in the perfumes and fragrances category, emulsifiers are able to offer emulsification as well as emolliency in the product.
Natural emulsifiers have a much higher penetration rate in personal care than in other industrial applications. Natural ingredients account for approximately 60% of emulsifier consumption in the United States, one of the largest markets for cosmetic products.
This can be attributed to rising customer demand for natural and non-toxic products, as well as the industry’s shift towards sustainable and environmentally friendly ingredients. Leading companies such as L’Oréal and Unilever have made long-term commitments to increase the use of renewable or biodegradable ingredients, following the same line of thought.
Leading emulsifiers of the industry
Glycol derivatives: PEG (polyethylene glycol) and PPG (polypropylene glycol) derivatives are well-known synthetic emulsifiers that are widely used in cosmetics. PEG-40 Hydrogenated Castor Oil is a popular emulsifier in this category, with uses ranging from skincare to deodorants and antiperspirants. These emulsifiers are popular due to their low cost and multiple functional properties.
However, there is an emerging trend towards using PEG-free products, substituting these ingredients with environmentally friendly alternatives. This trend is driven by concerns about pollution caused by the ethoxylation reaction. Because of its carcinogenicity and low biodegradability, 1,4 dioxane, a trace contaminant in the production process of such ethoxylated emulsifiers, raises health as well as environmental concerns.
Polysorbates: Polysorbates are derived from ethoxylated sorbitan esterified with fatty acids. Polysorbate 20, polysorbate 40, polysorbate 60, and polysorbate 80 are emulsifiers that are commonly used in cosmetics and skin care products, of which Polysorbate-20 is used the most in lotions, creams, and gels. They are also popular solubilizers and are widely used to dissolve fragrance components in perfumes.
SLS and SLES: Sodium Lauryl Sulphate is a popular synthetic emulsifier used widely in hair care and oral care products, derived from petroleum or from natural sources such as coconut or palm oil, because of its emulsification as well as foaming and cleansing properties. SLES is made by the ethoxylation of SLS. It is a milder ingredient than SLS, but because of the ethoxylation process, it is not considered sustainable and is even classified as ecotoxic by REACH.
However, due to rising customer concerns about SLS’s harshness on the skin and environmental concerns related to SLES, a sulphate-free trend has emerged, with multiple leading players such as P&G, Unilever, Estee Lauder, Sensodyne, etc., launching sulphate-free products such as shampoos, toothpastes etc.
Lecithin: Lecithin is one of the most widely used natural emulsifiers in the personal care industry, accounting for approximately 6% of total global emulsifier consumption. Lecithin has a long history of use in the industry, which is expected to grow as demand for natural beauty products rises. It is a multifunctional ingredient that performs emulsification, emollience, dispersion, rheology modification, and more.
Soy and sunflower are the most common sources of lecithin in personal care products. Lecithin is widely used in skincare and cosmetic products, primarily as an emollient and secondary emulsifier. Apart from emulsification, it is also used in shampoos, serums, and hair mask products for texture improvement and hair nourishment.
There are three types of modified lecithin used in personal care: hydrogenated, hydroxylated, and lysolecithin. These modifications improve lecithin’s properties, such as hydrogenated lecithin’s oxidative stability and hydroxylated lecithin’s water solubility, making them suitable for cosmetic applications. Because of its low HLB value, it is better suited for o/w products such as creams and lip products. However, it also works well in w/o emulsions when combined with other emulsifiers.
Some companies may prefer to avoid soy lecithin in soy-free formulations because it can cause allergies. It may be replaced with other sources of lecithin (sunflower/ corn) or formulated without lecithin.
The price, effectiveness, and stability of ingredients are the most important factors in selecting ingredients for product formulation. Certain leading synthetics, such as glycol derivatives and polysorbates, are thought to be cost-effective. However, due to a growing emphasis on the naturalness and sustainability of products, companies are increasingly using ingredients such as lecithin, cetearyl alcohol and glyceryl stearate.
Manufacturers are actively looking to switch to natural alternatives for synthetic ingredients. They are also working on solutions to use natural raw materials instead of synthetic petroleum or similar materials for the production of synthetic emulsifiers like SLS.
Many new product launches in personal care applications claim high biodegradability, for example, Unilever’s Love Beauty and Planet offers 100% biodegradable hair care products. Plant-based ingredients are also becoming more popular as ethical consumers seek out cruelty-free products.
Food-upcycled emulsifiers are also slowly making their way into the personal care space in order to reduce food waste and increase the use of biodegradable ingredients. Renmatix, a plant ingredient startup, offers Acer Rubrum Extract, an upcycled emulsifier for skin care applications.
The global emulsifier consumption is close to 2,000 KT, with food and feed applications accounting for the majority of the market share. However, personal care is one of the few industries that is distinguished by the widespread use of natural emulsifiers.
Emulsifiers are expected to grow significantly in the coming years as a result of ongoing innovation and high demand. However, less growth is expected for synthetic emulsifiers due to environmental concerns and regulatory restrictions affecting emulsifiers such as PEG derivatives and SLS.
Emerging industry trends and a growing emphasis on sustainability are driving their growth as a replacement for their synthetic counterparts.
This article was originally published in Personal Care Magazine, written by Dwiti Gaggar, Associate Consultant, ChemBizR.