الفهرس 
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Abstract
The term emulsion is used to describe a dispersion of one liquid into another. These liquids are mutually Immiscible with one another. Generally the phases are water (w) and an organic fluid with low dielectric constant which is usually termed as oil (0). The phase which is present in the form of finely divided DROPlets is called the internal or disperse phase, while the other in which these DROPlets are suspended is termed the external phase or dispersion medium. Thus depending on the state of dispersion an emulsion could be either 0/w or w/0 type. As a result of the dispersion of two phases, the interface bet¬ween them, and accordingly the free energy,is largely increased. Since the influence of the increase of entropy by dispersion is less pronounced, an increase in the free energy of the system results, consequently in thermodynamic sense, an emulsion is an unstable system and, therefore, possesses a natural tendency to break. Temporary emulsions which are obtained by simple dispersion of two pure liquids (without any stabilizer) are termed as dilute emulsions or hydrosol.
Ostwald^ ’ first, pointed out the existence of two distinct emulsion types, i.e., either oil-in-water (0/w)
(oil being the disperse phase), or water-in-oil (w/0) (water