SHAMPOOS
Composition and Function: Shampoos are used to remove excess oil, dirt and skin debris from the hair. 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 a 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%. Nonionic surfactants which have good detergency but generally poor foaming characteristics are usually blended with another detergent which is a good foamer. Nonionics are frequently used to reduce eye irritation and sting. Higher molecular weight ethoxylates like G-4280 PEG (80) sorbitan laurate function as shampoo thickeners and foam stabilizers. Shampoos usually include modifying agents such as opacifiers, clarifying agents, antifreezes. conditioning and finishing agents, sequestrants, thickening agents, proteins, foam builders, and antidandruff agents. The use level of these modifiers is usually about 1% to 10%. Formulation: A liquid shampoo which has a low order of eye irritation can be made by carefully selecting the detergents. In the following baby shampoo, the combination of anionic and amphoteric surfactants with G-4280 produces a formula which should be mild, effective and esthetically appealing.
Preparation: Mix (A) with gentle stirring and heat until homogenous. Heat to around 60°C and add (B) and continue stirring. When clear, cool and adjust pH to 6.8 with (C). Replace water lost by evaporation. TWEEN(r) 20 Polysorbate 20 has been used as an effective anti-irritant for shampoos. Formula HC-6 illustrates this application.
Preparation: Mix (A) with gentle stirring and heat until homogenous. Adjust pH to 5.0 to 5.5 with (B). Frequently, conditioning agents can be included in a shampoo formula to improve wet and dry compatibility. FORESTALL™ Soyaethyl morpholinium ethosulfate is a water-soluble conditioning agent which is compatible with many anionic surfactants. Thus, it is possible to formulate clear conditioning shampoos.
Preparation: Mix (A) with heat and gentle agitation until homogenous. Add (B). Adjust pH to 5.5 with (C). |
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