Core tip: As the core performance index of surfactants, HLB directly determines the stability of the emulsifying, cleaning, and solubilizing system. Its application logic runs through all fields of beauty personal care, care and industrial emulsification. “Matching” and “compounding” are the key to its value.The application of surfactants is everywhere, and HLB (Hydrophilic-Lipophilic Balance), the core index that determines its performance, is becoming a key reference for industry research and development, production and selection.
For the majority of customers of cosmetics, personal care, care and industrial emulsification systems, an in-depth understanding of the application logic of HLB value can not only avoid the risk of formula failure, but also realize the dual upgrade of product performance and experience.The core role is：
• Quantify the hydrophilic and oleophilic tendencies of surfactants
• Provide a clear direction for the formulation design of different systems
• Directly determine the applicable scenarios and product characteristics of surfactants
I.HLB value level
The core role of HLB value is to define the hydrophilic and oleophilic tendency of surfactants through the numerical range. The law generally followed in the industry: the lower the HLB value, the more oleophilic the surfactant is, and the higher the HLB value, the more hydrophilic it is.
Common intervals and application guidelines for HLB values (industry general standards)：
•1-3 (strong oleophilic): defoaming, W/O emulsification system
•3-6 (oily): W/O Emulsifier, suitable for heavy and water-resistant products •7-9 (intermediate type): wetting, spreading, improving product applicability
•8-18 (water-based): O/W emulsifier to create refreshing lotions and care products
•13-18 (strong hydrophilicity): solubilizing and cleaning products to improve cleaning power and solubility
This also explains why the HLB values of PEG emulsifiers commonly used in the industry are high, Span HLB values are low, and Tween HLB values are higher-the core reason lies in the difference in ethoxy content. The more ethoxy, the stronger the hydrophilicity, and the higher the HLB value.
Give an example：
• peg-60 Hydrogenated castor oil (HLB 15-17): It is commonly used in solubilizing cleaning products to efficiently pull oil-soluble ingredients such as flavors and essential oils into the water phase system. • Span 60 (HLB 4.7): Strong oleophilic, is the core raw material of the W/O emulsifying system, suitable for heavy creams.
In practical applications, the HLB value directly affects the product form and use experience, and the typical selection logic in the field of beauty and personal care：
• Refreshing moisturizing lotion: Use O/W emulsifier with HLB value of 8-12
• Waterproof, sunscreen, hair dye cream: use W/O emulsifier with HLB value of 3-6
This kind of selection logic based on HLB value has become the industry consensus and the basis for ensuring product quality.
II.The core value of HLB value
For customers in the fields of cosmetics, personal care, care and industrial emulsification, the importance of HLB value is essentially reflected in its decisive role in system stability-it directly affects the direction of emulsification, product skin feeling, cleanliness, water resistance and other core properties, and these properties are the key to product competitiveness.
Core influence 1: Emulsification direction (the primary consideration in formula design)
(1) Low HLB value (partial oleophilic)：
• Easy to build W/O emulsification system
• Suitable for heavy cream, waterproof sunscreen, hair dye cream and other products
• Water resistance, good sealing, can provide long-lasting moisturizing protection
Example: Classic cold cream (cold cream), the emulsifier HLB value is 3-5, to achieve uniform dispersion of the oil phase, bringing a heavy and moisturizing feeling.
(2) High HLB value (partial hydrophilic)：
• Easy to build O/W emulsification system
• Suitable for refreshing products such as lotions, shampoos, cleansing products, etc.
• Easier to wash, no sticky feeling after use, suitable for “refreshing skin care” needs
Example: Daily cleanser, using high HLB value surfactants, strong cleansing power and easy to rinse, no residue.
There is a simple and easy-to-understand technique in the industry that can quickly understand the relationship between HLB value and product characteristics: “The higher the HLB, the more refreshing and easier the system is to wash, and the lower the HLB, the heavier the system is and the more water-resistant it is.”
Core impact two: Multiple performance adaptation
• Refreshing feeling: high HLB→ refreshing water feeling,low HLB→ heavy and oily
• Cleaning and foaming: high HLB is more soluble in water, has better cleaning power and foaming volume, and is suitable for care and cleansing products
•Solubilizing ability: High HLB can achieve solubilizing of flavors and essential oils, and help product transparency
• Water resistance: low HLB, strong water resistance, suitable for sunscreen, makeup, and sweat-proof systems
It is worth noting that the HLB value is equally important in the field of industrial emulsification and water treatment.For example, in the preparation of a new type of polymer emulsion, an emulsifier adapted to the HLB value needs to be selected according to the oil phase characteristics. The dispersion stability of ammonia acetate copolymer is closely related to the HLB value. Matching the appropriate HLB value can ensure uniform and stable emulsion and avoid stratification and oil bleaching.
III.Cracking cognitive misunderstandings: The higher the HLB, the better, matching is the key
Common misunderstanding: The higher the HLB value, the stronger the emulsifying ability
Correct understanding: The core value of HLB value lies in matching, not high or low-the HLB value of surfactants needs to be matched with the required HLB of the oil phase, which is the key to the stability of the system.
The so-called “Required HLB” refers to the HLB value of surfactants required for each oil to achieve the most stable emulsification.The required HLB values of different oils and fats vary significantly：
•Mineral Oil: ~10.5
•Glyceryl Stearate: ~3.8
•Silicone oils (such as Dimethicon): usually lower If the HLB value deviates too much, it will cause the emulsifying system to be unstable. Specific problems include：
• Layering, bleaching oil
• Viscosity drop
• Hot and cold cycle failed
IV.Common strategies in the industry: compound HLB to take into account diverse performance requirements
The core purpose of the complex configuration: to adjust the overall HLB value of the system to achieve multiple performance balance.
Common compound combinations：
• Span 60 and Tween 60
• Glyceryl Stearate and PEG-100 Stearate
Compound advantage：
• Accurately match the HLB value required for the oil phase to improve system stability
• Improve the skin feel of the product and avoid being too heavy or too refreshing
• Reduce product irritation
Complex HLB can also solve the needs of special scenarios, such as：
• Care products containing electrolytes: improve the electrolyte stability of the system and avoid stratification and thinning
• Industrial complex oil phase system: improve emulsification efficiency, reduce production costs, and ensure product consistency
V.Professional cognition upgrade: HLB is not a universal indicator, it needs to be comprehensively evaluated
Although the HLB value is the core reference for surfactant applications, it is not a panacea.In the development of real-world formulas, there are many factors that determine the stability of the system. The HLB value is only one of them, and it needs to be combined.：
• Emulsifier structure
• Saturated/unsaturated chain, EO number
• Electrolyte tolerance, liquid crystal structure, polymer network
• Silicone oil compatibility, temperature, shear process
Summary
Taken together, the HLB value plays an irreplaceable role as the core parameter. The core values include：
• Help formulators quickly judge the adaptability of raw materials and clarify the direction of product application
• Avoid the risk of formula failure and reduce R&D costs
• Help customers understand the characteristics of raw materials and achieve accurate selection
But we must be clear that the HLB value is only the starting point of formula design, not the only determinant.A truly stable and high-quality product system needs to be comprehensively evaluated in combination with the HLB value required for the oil phase, the structure of the emulsifier, the conditions of use and the overall structure of the formula.
Hubei Mingya New Material Technology Co., Ltd.
