Theory In essence, shampoos are simply detergents.They are a different type of cleaning media than ordinary laundry or hand detergents because of their application to different types of hair. Shampoos are used to remove excess oil, dirt and skin debris from the hair known as sebum. A good shampoo will perform this function while leaving the hair manageable. These products should possess rich foaming action and rinse out easily. Various forms of shampoos are available, from clear liquids to opaque pastes. The primary ingredient of a shampoo is the detergent, either from an organic soap or a synthetic. Vegetable oil soaps, alkyl benzene sulfonates, sodium or triethanolamine alkyl sulfates, sulfated monoglycerides, sulfated oils and nonionics are typical. The concentration used varies with the individual detergent and the shampoo type and will vary from about 10% to 50%. Shampoos usually include modifying agents such as opacifiers, clarifying agents, antifreezes, conditioning a...