Span S-60 (chemical name: sorbitan monostearate, CAS number: 1338-41-6) is a classic nonionic surfactant produced by Guoli Chemical. Its molecular structure contains both a hydrophilic sorbitan ring and a lipophilic long-chain stearic acid group, enabling it to form a strong interfacial film at the oil-water interface, thereby preparing a stable water-in-oil (W/O) emulsion system. This property makes it an indispensable functional component in many industrial formulations.
Another significant advantage of Span S-60 is its excellent compatibility flexibility. It can be used alone as the primary emulsifier or combined with hydrophilic surfactants such as the Tween series. By adjusting the ratio of the two, the HLB value of the system can be precisely controlled, achieving accurate design of the emulsification system to meet the formulation needs of different products. Meanwhile, this product maintains stable performance over a wide pH range and under hard water conditions, showing good tolerance to acids, bases, and hard water.
In terms of safety, the oral LD₅₀ of Span S-60 in rats is greater than 15,000 mg/kg, classifying it as a low-toxicity substance. It is widely recognized and used in fields directly related to human health, such as food (as E491), cosmetics, and pharmaceuticals. In addition to its emulsifying function, this product also offers multiple functions including dispersion, solubilization, and lubrication, which can simplify formulations and enhance overall product performance, making it a multifunctional surfactant.
| Characteristic | Description |
|---|---|
| Emulsification Type | Efficient W/O (water-in-oil) emulsifier |
| Chemical Name | Sorbitan monostearate |
| CAS Number | 1338-41-6 |
| Ionic Type | Nonionic surfactant |
| Compatibility | Can be compounded with Tween series to flexibly adjust HLB value |
| Chemical Stability | Resistant to acids, bases, and hard water |
| Toxicity Level | Low toxicity (rat oral LD₅₀ > 15,000 mg/kg) |
| Food Additive Code | E491 |
| Multifunctionality | Integrated emulsification, dispersion, solubilization, and lubrication |
Span S-60 is widely used in the following fields:
Span S-60 is classified under GHS as Skin Irritation Category 2 (H315: Causes skin irritation), Eye Irritation Category 2 (H319: Causes serious eye irritation), and Specific Target Organ Toxicity Single Exposure Category 3 (H335: May cause respiratory irritation). It is recommended to wear chemical protective gloves, goggles, and necessary respiratory protection during handling, and to use in a well-ventilated area. Storage temperature is recommended to be below 35°C, avoiding direct sunlight and extreme temperature fluctuations. For detailed safety information, please refer to the Safety Data Sheet (SDS).