Evaluating formulations – Establishing salient specifications


SurfaTech Corporation, Lawrenceville, Ga, USA


The development of a commercially successful cosmetic formulation requires chemist to consider many different properties that the consumer demands. These include the requirement the product functions as required. This first requirement is clearly critical to consumer acceptance, a shampoo that does not clean hair will not be successful, but this attribute alone is just one step. The formulator must deal with a number of other formulation issues including secondary properties of the formulation including wetting viscosity, aesthetics, preservation, color and odor. The evaluation of these issues is complicated by the fact there is no simple analytical test available. If the product is an emulsion the formulator must deal with the product’s properties as applied, but during application and finally performance after rub-out. This article will look at some predictive tests that will help minimize problems related to oxidation, including odor and color formation.
There are many properties that can be measured using existing analytical methods that are simple, for example titrations. While simple and necessary, they can often not provide vital information on the stability of the formulation. The formulator must develop salient specifications, that is specifications and test methods that describe essential properties that ensure that intended use of the formulation can be satisfactorily realized.

The development of cosmetic product requires the consideration of a large number of properties that will determine the commercial success of a particular formulation. During the development process, the salient specifications and the methods of testing for them need to be developed. It is crucial for the formulator to deal with a variety of potential issues that can occur during the products life and anticipate and deal with these. As the market moves to more biodegradable ingredients, preservation will become more and more an issue. Simply put, when we require biodegradable ingredients, we need to select preservatives that are potent enough to prevent biodegradation during the products shelf life, but in addition do not interfere with the functionality of bacteria that are biodegradation process.


The formulator needs to consider a variety of required properties that are required in a formulations. Many times compromises need to be made to provide an optimized formulation. One example is a request for a biodegradable well preserved formulation. Clearly, a very potent preservative can interfere with the bacteria that biodegrade formulation ingredients. The ...