Dispersing agents lecithin

E>eciease the rale of settling and the degree of flocculation adding surfactants or dispersing agents (lecithin, oleic acid, ethyl alcohol). 

Purified soybean lecithin Dispersing agent, emulsifying agent, solubilizer, stabilizer iv... 

MDIs, be they solution or suspension formulations, typically contain a surfactant or dispersing agent. These materials generally need to have some solubility in the propellant blend. Commonly used surfactants include sorbitan trioleate (SPAN 85), oleic acid, and lecithins, at levels between 0.1% and 2.0% wt/wt [40]. These agents are required both to maintain the disperse nature of the drug (in suspension formulations) and to provide lubrication for operation of the metering valves. However, these surfactants have poor solubility in the HFA... 

Most lecithin is utilized for nonfood purposes, as emulsifiers, dispersion agents, adhesives, or lubricants. It is added to coatings, such as paints, waxes, and polishes. Its use in the cosmetic and pharmaceutical industries is also important (Wendel, 2001). 

Surfactants are often required to wet the powder for proper dispersion. ISO 14887 provides a comprehensive listing of commercially available dispersing agents. Some instrument manufacturers (Horiba, for example) recommend surfactants including Micro 90 solution (also good for cleaning the instrument), Triton X-100, Igepal CA-630, Tween 80, and lecithin. 

Some of the major functional uses of lecithin products are as (1) emulsifiers in food emulsions, (2) solubilizing agents for various compounds in aqueous systems, (3) sol dispersing agents, and (4) foaming and defoaming agents. 

Plastics. Lecithin (0.5—1.5%) is used for pigment dispersion and as a shp or release agent. It also may be sprayed on molds. It has surfactant effects in organosols and plastisols (see Surfactants). 

The lecithin serves as an emulsifying agent that allows the aqueous and lipid phases to be dispersed in each other and increases the time required for phase separation. 

Acetylated lecithins have improved fluid properties, improved water dispersibility, and are effective oil-in-water emulsifiers for a wide variety of food formulations (56, 58). Moderately and highly acetylated lecithins are resistant to heat and can be repeatedly heated and cooled without darkening. The intended uses for minimally acetylated products are in infant foods, coffee whiteners, meat sauces, and gravies, and for oil-in-water cosmetic emulsions. Moderately and maximally acetylated products are used in cheese sauces, release agents in pumpable and aerosol formulations, and shortenings. 

Producing low-viscosity, fluid lecithins as wetting, dispersing, and release agents. 

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