ABSTRACT
Thickening agents, or viscosity-enhancing agents, are an important group of raw materials that determine the final form and function of a personal care formulation. Ethylcellulose is an oil-thickening and film-forming additive. Due to its versatility and broad compatibility with a wide range of oils, it provides formulators with flexibility and new options for thickening and formulating with oils, ranging from a slightly thickened oil to a transparent oil gel. The most common way to achieve maximum thickening from cross-linked polymers is by converting the acidic carbomers to a salt. Once a neutralizer is added to the dispersion, thickening gradually occurs and the optimum viscosity is typically achieved at a pH of 6.5–7.5. Fumed silica is a good thickener for non-polar systems, but it is not suitable for thickening aqueous systems. Typical non-ionic thickening agents for surfactant systems can be generally divided into two groups: hydrophobic and hydrophilic types.
