Question

What are the main features of Span S-40?

Answer
2026-05-17 官方文档 司盘S-40

Span S-40 is a high-performance nonionic W/O emulsifier, appearing as a light yellow waxy solid, with excellent chemical stability, broad formulation compatibility, and extremely low safety risk. It is a versatile functional surfactant widely used in cosmetics, food, pharmaceuticals, pesticides, textiles, and other industries.

Detailed Description

Span S-40, chemically known as sorbitan monopalmitate, is a nonionic surfactant. Its molecular structure imparts unique lipophilic properties, enabling efficient formation and stabilization of water-in-oil (W/O) emulsion systems. The product appears as a light yellow waxy solid, remaining solid at room temperature for easy storage and transportation.

As one of the core products of Guoli Chemical, Span S-40 performs exceptionally well in complex formulation systems—it can withstand interference from acids, alkalis, and hard water, maintaining stable emulsifying capacity under various process conditions. Additionally, it is well compatible with various ionic and nonionic auxiliaries, offering formulation engineers great design flexibility. Especially when used in combination with the Tween series, the HLB value can be flexibly adjusted, enabling transitions from W/O to O/W emulsion systems.

In terms of safety, the rat acute oral LD₅₀ of Span S-40 is greater than 10 g/kg, classified as practically non-toxic. Its primary skin irritation index is 0, with no irritation or mutagenicity. It complies with food additive standards such as FDA 21 CFR 172.842 and can be safely used in food, cosmetics, and pharmaceutical fields.

Technical Parameters

ParameterValue
Chemical NameSorbitan monopalmitate
CAS Number26266-57-9
AliasesSorbitan monopalmitate, Span 40, Arlacel 40
Product TypeNonionic surfactant
AppearanceLight yellow waxy solid
Emulsion TypeWater-in-oil (W/O) type
Acute Oral Toxicity (Rat)LD₅₀ > 10 g/kg (practically non-toxic)
Skin IrritationNon-irritating (primary irritation index: 0)
Regulatory CertificationFDA 21 CFR 172.842

Note: Specific physical and chemical indicators such as HLB value, hydroxyl value, and saponification value are not available here. It is recommended to contact the Guoli Chemical technical team for factory testing standards.

Application Suggestions

With its W/O emulsifying characteristics, Span S-40 has broad application value in the following fields:

  • Cosmetics and Personal Care: Used as the primary emulsifier in W/O creams and lotions, providing a fine skin feel and excellent stability.
  • Food Industry: Used as an emulsifier and stabilizer, suitable for baking fats, whipped creams, and protein beverages.
  • Pharmaceutical Preparations: Used as an emulsifying base for creams and suppositories, improving drug dispersion uniformity and bioavailability.
  • Pesticide Environmentally Friendly Formulations: Used as an emulsifier and dispersant in emulsifiable concentrates, water emulsions, and suspension concentrates, enhancing wetting and spreading of the spray liquid.
  • Textile Industry: Used as a softener and antistatic agent in spinning oils, imparting good smoothness and cohesion to fibers.
  • Plastic Industry: Used as an internal antistatic agent and anti-fogging agent, migrating to the surface of plastic films to eliminate static and prevent fogging.
  • Coatings and Inks: Used as an efficient pigment dispersant, reducing grinding time and preventing pigment flocculation and re-agglomeration.

Precautions

Operational Protection: Although this product has extremely low toxicity, it is still recommended to wear a particulate respirator (when dust is generated), protective gloves, and safety glasses during operation to avoid repeated contact leading to skin defatting. Wash hands and exposed skin thoroughly after work.

Storage Conditions: Store sealed in a cool (recommended below 35°C), dry, and well-ventilated warehouse, away from heat sources, open flames, and direct sunlight. Keep away from incompatible substances such as strong oxidizing agents and strong acids.

Emergency Treatment: In case of eye contact, immediately flush with running water for at least 15 minutes; if ingested, rinse mouth with water, do not induce vomiting for unconscious persons, and seek medical attention promptly with the safety data sheet.