Heat has been used to style hair for millennia. However, when we heat-style our hair we can cause lasting damage.

There are a number of approaches to protecting the hair from heat styling damage, including the dissipation of heat with water applied to the hair surface, alteration of heat transfer to the hair through sticking fibers into bundles, and creating insulating surface films.

The two most popular techniques used at TRI to support heat protection claims are Differential Scanning Calorimetry (DSC) and automated repeated grooming (hair breakage) testing.

DSC is a very sensitive technique that can detect small levels of heat protection. For this reason, it is often our method of choice for clients. However, the drawback of DSC is that any effects seen using this method do not easily translate to consumer-perceptible levels of hair damage, and that the degree of change in the keratin denaturation transition does not, for example, translate directly to hair breakage. DSC, therefore, whilst very sensitive, can only give a yes/no answer: either a treatment significantly reduces heat styling damage, or it does not.

Automated repeated grooming (hair breakage) measurements, in contrast to DSC, are less sensitive to subtle changes in heat damage, but do relate more obviously to the consumer perception of hair damage and can be used for quantitative claims.