Span S-40 (Sorbitan monopalmitate, CAS No.: 26266-57-9) has extremely high toxicological safety, with an acute oral LD₅₀ greater than 10 g\/kg in rats and a primary skin irritation index of 0. Although its toxicity is very low, good industrial hygiene practices should still be followed during operation, with the core focus on dust control. This product is a waxy solid that may generate dust during weighing, feeding, or crushing processes. Inhalation may cause mild discomfort, so it is crucial to maintain ventilation in the workplace.
In daily use, the focus of personal protection is on the eyes and hands. It is recommended to wear safety goggles to prevent accidental splashing of solid particles into the eyes, which may cause temporary discomfort; wear general protective gloves to prevent skin defatting due to repeated or prolonged contact. Eating, drinking, and smoking are strictly prohibited in the operating area, and hands and exposed skin should be thoroughly washed after work.
In terms of storage, this product is chemically stable, but it should be stored in a cool (recommended temperature below 35°C), dry, and well-ventilated warehouse, away from heat sources, open flames, and direct sunlight. The packaging container must be kept sealed to prevent moisture absorption. After opening, it should be promptly resealed and stored upright. Special attention should be paid to avoiding mixing Span S-40 with incompatible substances such as strong oxidizing agents and strong acids.
| Parameter | Value |
|---|---|
| Appearance | White to light yellow waxy solid |
| Melting point | 45~47°C |
| Flash point | >200°C |
| Active content | ≥99% |
| HLB value | 6.7 |
| Iodine value | ≤10 |
| Moisture | ≤1.5% |
| Heavy metals | ≤10 mg\/kg |
| Arsenic | ≤2 mg\/kg |
| Recommended storage temperature | Below 35°C |
Span S-40 is a typical water-in-oil (W\/O) type emulsifier with an HLB value of 6.7. In formulations, it is often used in combination with Tween series with high HLB values to achieve a wider range of emulsification effects. In cosmetic creams, food baking oils, pharmaceutical ointments, and pesticide emulsifiable concentrates, it is recommended to dissolve this product in the hot oil phase first before emulsification. When used as an antistatic agent or anti-fog agent in the plastics industry, it can be added internally, leveraging its migration property to exert long-lasting effects. When used as a pigment dispersant in coatings and inks, it is recommended to add it during the grinding stage to effectively shorten grinding time and prevent pigment re-agglomeration.