Oil in water (O/W)
Emulsifier has become one of the most commonly used emulsification systems in external face cream and lotion due to its refreshing texture, rapid skin absorption and core moisturizing effect. Its essence is a stable system that disperses the oil phase in the water phase, with oil as the internal dispersed phase and water as the continuous external carrier. Compared to the oil in water system, it is not only easier to operate, but also has a fresher skin feel when used, making it the most widely used formula type in cosmetics production. In some skincare formulas, film-forming or stabilizing ingredients such as
Sodium acrylate are also added to further enhance the texture and extensibility of the system.
Two core categories: non-ionic and anionic O/W emulsifiers
According to their charge characteristics, oil in water (O/W) emulsifiers are mainly divided into two categories: non-ionic and anionic. The two complement each other in terms of formula compatibility and functional positioning, together forming a diversified emulsification solution.
1. Non ionic O/W emulsifier: a mild and compatible preferred choice
Non ionic O/W emulsifiers with glycerol esters and polyethers as the core have become the first choice for sensitive muscle products and multiphase lotion systems due to their low irritation and strong compatibility. Its molecular structure is uncharged and has high tolerance to electrolyte and pH changes. It can coexist friendly with active ingredients such as vitamin C derivatives and ceramides, and will not cause system instability due to ion interactions.
Typical products such as OIL REE ® MY965 (PEG-100 stearate/glyceryl stearate) is designed specifically for non-polar oils and has excellent self emulsifying ability. Even though the proportion of mineral oil and silicone oil in the formula is very high, it can also create a delicate and stable lotion, and has excellent electrolyte resistance. It is especially suitable for functional skin care products containing hyaluronic acid, nicotinamide and other ingredients. The recommended addition amount is 1% -5%. Another OIL REE ® MY9200 (PEG-20 stearate) focuses on soft, smooth and smooth skin. When used together with cetearyl alcohol, it can form a thin and breathable film on the skin surface, giving consideration to the moisturizing effect and no sticky feeling. It is suitable for creating a light moisturizing face cream in autumn and winter.
2. Anionic O/W emulsifier: an efficient and multifunctional choice
Anionic O/W emulsifiers, represented by phosphate esters, exhibit outstanding performance in powder dispersion, phase transfer, and waterproofing due to their negatively charged molecular structure and high HLB value. This type of emulsifier can evenly wrap sunscreen and makeup powder through charge repulsion, preventing particle aggregation and forming a waterproof film on the skin surface. It is particularly suitable for products with specific needs such as sunscreen, makeup remover, and natural cream.
For example, PHSPTER ™ 94TS (Laureth-4 phosphate ester) has significantly improved mildness compared to traditional anionic emulsifiers, with excellent phase transfer and dispersibility. In sunscreen formula, it can evenly disperse zinc oxide and titanium dioxide, avoiding whitening and clumping; With OIL REE ® When used in combination with MY943 (sorbitol polyether-30 tetraoleate), it can enhance the oil solubility of makeup remover products and easily remove waterproof makeup. The recommended dosage is 1% -20%. And PHSPTER ™ 922P (C20-22 alkyl phosphate/stearyl alcohol phosphate/behenyl alcohol) optimizes the thickening effect on the basis of waterproofing, without the need for additional thickeners, allowing natural and sunscreen to achieve the desired texture and reduce formula complexity. The recommended addition amount is 1% -5%.
Three core advantages: balance and stability, skin feel and functionality
The value of oil in water (O/W) emulsifiers lies not only in the fusion of oil and water, but also in achieving a triple balance of stability, skin feel, and functionality through technological design, providing customized solutions for different categories of cosmetics.
1. Excellent stability, suitable for multiple formulas
O/W emulsifier disperses the oil phase into small oil droplets by reducing the interfacial tension between oil and water, and then forms a dense adsorption film on the surface of the oil droplets to prevent particle collision and agglomeration. Non ionic emulsifiers rely on the polyoxyethylene chain segments and glyceride groups in their molecules to form a protective barrier on the surface of oil droplets, maintaining system stability; Anionic emulsifiers further enhance the dispersibility of oil droplets through charge repulsion, especially in high proportion powder sunscreen formulations, which can avoid delamination caused by gravity settling. In addition, OILREE ® O/W emulsifiers such as MY968 (glycerol stearate citrate/PEG-100 stearate/benzyl alcohol) also have post thickening ability, and the viscosity of the emulsion system gradually increases over time, ultimately forming a fine and dense texture, reducing dependence on thickeners such as carbomer.
2. Customizable skin feel, suitable for different scenarios
The molecular structure of O/W emulsifiers directly affects the skin feel of products: the longer the polyether chain segment in non-ionic emulsifiers, the fresher the skin feel. For example, MY965 with PEG-100 chain segments can be easily pushed away when the emulsified lotion is applied, which is suitable for oil control lotion in summer; The MY9200 containing glycerol ester and fatty alcohol can bring cream like touch, which is more suitable for autumn and winter moisturizing face cream. Anionic emulsifiers are often compounded with alcohols to create a refreshing and breathable waterproof film, which can be used in sunscreen products to avoid stuffiness. At the same time, the water in oil structure of the O/W system can accelerate the penetration of oil phase components, allowing fat soluble active ingredients such as vitamin E and plant essential oils to be absorbed by the skin faster and reducing surface residue.
3. Strong compatibility and adaptability to diverse needs
Nowadays, electrolytes such as sodium hyaluronate and amino acids are often added to skincare products. Traditional emulsifiers are prone to breaking down due to ion interactions, while O/W emulsifiers have high tolerance to electrolytes. For example, MY965 can still remain stable in a formula containing 2% hyaluronic acid; Although anionic emulsifiers are sensitive to strong electrolytes, they can also be adapted to oil control formulations containing niacinamide and zinc ions by compounding with non-ionic emulsifiers. In addition, O/W emulsifiers can be compatible with various active substances, such as MYPGI3610, which can coexist with retinol and peptide components, slowing down the oxidation of active substances through emulsification and extending product shelf life.
Widely applicable scenarios: running through the entire category of beauty and skincare
With its flexible adaptability, O/W emulsifiers have penetrated into multiple fields such as skincare, sun protection, makeup, and makeup removal, becoming a key ingredient driving product innovation.
In skin care products, non-ionic O/W emulsifier is the core component of face cream and lotion - MY9200 is suitable for moisturizing face cream, and MY968 is suitable for essence milk; In sunscreen products, anionic 94TS is responsible for dispersing sunscreen powder, while non-ionic MY965 assists in enhancing skin feel. The combination of the two can create high-quality sunscreen; In the field of cosmetics, 922P has become the best choice of plain cream and liquid foundation by virtue of its thickening and waterproof properties, which can make the toner evenly dispersed and improve the makeup fit; In makeup removal products, 94TS has the ability to quickly dissolve waterproof makeup, and when combined with mild surfactants, it can achieve a balance between cleaning and moisturizing. (Note: The chemical substance CAS number 9005-67-8 mentioned in the article corresponds to the relevant emulsifier raw material standard number)
Future development direction: green, multifunctional, intelligent
In the future, the development of O/W emulsifiers will focus on three major directions: firstly, greening, using more plant-based raw materials, and reducing dependence on petrochemical components; Secondly, it is multifunctional, integrating functions such as emulsification, moisturizing, and repairing, simplifying the formula; The third is intelligence, which achieves temperature responsive emulsification through molecular design, such as maintaining stability at low temperatures and rapidly breaking down and releasing active ingredients upon contact with the skin.
In the segmented field, the demand for oil in water emulsifiers is particularly prominent in the cosmetics industry. According to global data consulting firms, the demand for water in oil emulsifiers in the global market is expected to double by 2030 compared to 2025. Especially with the increasing demand of consumers for environmentally friendly, healthy, and sustainable products, companies are developing new non-toxic and biodegradable emulsifiers, which has also brought new growth points to the industry.
Yichang Mingya New Material Technology Co., Ltd.
