span is synthesized by fatty acid and sorbitol, which is a nonionic surfactant. as a lipophilic emulsifier, it is full of diverse fatty acid, due to the hlb value is 1.8 to 8.6, it can be dissolved in organic solvents. when it is used in food product, it can make the cream more emulsive and lustrous, due to their emulsification, stabilization and frothing. in these processing, the s-40, s-60 and s-65 is make a leading actor of emulsification and thickening, the s-80 and s-85 improve the luster. anyhow, it is can widely used in many fields, such as auxiliaries for textile ( oil solution, softening agent), metal processing aids (antirusting, cutting agent), etc. the seriers including: span-20, span-40, span-60, span-65, span-80, span-85