Span S-85 is a classic nonionic surfactant produced by Haian Guoli Chemical Co., Ltd., with CAS number 26266-58-0, molecular formula C₆₀H₁₀₈O₈, and molecular weight approximately 957. The product appears as a viscous oily liquid ranging from amber to brownish-yellow, with an extremely low hydrophilic-lipophilic balance (HLB=1.8), exhibiting strong lipophilic characteristics. Due to its molecular structure containing one sorbitan hydrophilic group and three oleic acid long-chain lipophilic groups, it has excellent solubility and dispersibility in the oil phase, significantly reducing oil-water interfacial tension and forming stable water-in-oil emulsions.
Span S-85 offers good chemical inertness and broad compatibility, withstanding acidic, alkaline, and hard water environments, maintaining stable activity under a wide range of conditions, and is well compatible with various oils, waxes, and active ingredients. The product has an active content ≥98%, moisture content ≤1.5%, acid value ≤15 mgKOH/g, saponification value 165~185 mgKOH/g, and hydroxyl value 50~80 mgKOH/g. Additionally, it is a low-foaming surfactant with a flash point above 200°C (open cup method), offering high safety in use, and is not classified as a hazardous chemical under GHS classification.
| Parameter Item | Technical Index |
|---|---|
| Chemical Name | Sorbitan trioleate (Sorbitan trioleate) |
| CAS No. | 26266-58-0 |
| Molecular Formula | C₆₀H₁₀₈O₈ |
| Molecular Weight | Approx. 957 |
| Ionic Type | Nonionic |
| Appearance (25°C) | Amber to brownish-yellow viscous oily liquid |
| HLB Value | 1.8 |
| Active Content | ≥98% |
| pH Value (1%~5% aqueous dispersion) | 5.0~7.0 |
| Acid Value | ≤15 mgKOH/g |
| Saponification Value | 165~185 mgKOH/g |
| Hydroxyl Value | 50~80 mgKOH/g |
| Iodine Value | 75~85 gI₂/100g |
| Moisture | ≤1.5% |
| Density (25°C) | 0.95~1.00 g/cm³ |
| Kinematic Viscosity (25°C) | 200~500 mm²/s |
| Low Shear Viscosity (25°C) | 200~400 mPa·s |
| Refractive Index (20°C) | 1.470~1.480 |
| Flash Point (Open Cup) | >200°C |
| Melting Point | <0°C (Liquid at room temperature) |
| Solubility | Easily soluble in oil, dispersible in water |
| Cloud Point | Not applicable (Oil-soluble, insoluble in water) |
| Foam Characteristics | Low foam |
| Hygroscopicity | Low |
| Heavy Metal Content | ≤10 mg/kg |
| Arsenic Content | ≤2 mg/kg |
| Free Alcohol Content | ≤2% |
| Chemical Stability | Stable at room temperature, avoid contact with strong acids and bases |
With its extremely low HLB value and strong lipophilicity, Span S-85 plays an irreplaceable role in many industrial fields:
Cosmetics and Personal Care: As a water-in-oil emulsifier, it is widely used in cold creams, moisturizing creams, massage creams, sunscreens, and foundation liquids, with a recommended dosage of 1% to 5% of the total formulation. It imparts a fine texture and excellent long-term stability to the cream, while improving spreadability and coverage. In color cosmetics, it can also be used as a pigment wetting and dispersing agent.
Pharmaceutical Preparations: Used in topical ointments, cream bases, and suppositories as a mild W/O emulsifier to promote uniform drug distribution and transdermal absorption, especially suitable for carrier systems of lipophilic drugs.
Industrial Applications: In metalworking, used in emulsified cutting fluids and rust-proof oil formulations; in the textile industry, as a component of synthetic fiber oils and antistatic finishing agents; in petroleum extraction, for emulsification stabilization of oil-based drilling fluids and fracturing fluids; in paints and inks, as a pigment wetting and dispersing aid; in pesticide formulations, as an emulsifier for emulsifiable concentrates (EC) and a co-formulant for suspension concentrates (SC).
Food Industry: In compliance with food additive regulations, it can be used in whipped cream, icings, shortenings, etc., to improve aeration and structural stability.