Shampoo and bath additives

Shampoo and bath additives
Thickeners
A high viscosity is often very important both for product stability and for handling of a cosmetic product. For shampoos, shower and foam bath products, viscosities between 400 and 4000mPas are typical. Pearlescent products should have a minimum viscosity of 2000 mPas to avoid precipitation. In the case of ether sulphate as the main surfactant, the thickening can easily be achieved by addition of electrolytes (chlorides of sodium, ammonium or magnesium, for example) to the formulation. The mechanism is by an increase in the size of the micelles. The thickening effect of alkanol amides is similar. Due to possible contamination with nitrosamines, low ethoxylated fatty alcohols such as the laureth-3 are recommended as replacements. These products are also good thickeners but, unlike the alkanol amides, they increase the cloud point of the formulations.
A different principle of thickening is obtained by the use of special, high molecular weight thickeners such as PEG-6000 distearate, talloweth-6O myristyl glycol or PEG-120 methyl glucose dioleate. The structure of talloweth-60 myristyl glycol with its hydrophobic ends is very similar to that of PEG-6000 distearate. An advantage is that it is an ether product which remains stable against hydrolysis at higher temperatures or extreme pH values.