Rheology is defined as the study of the deformation and flow of matter.1 The rheology of a fluid system governs both in-process efficiency and final product quality. It is therefore critical to the manufacturing of liquid personal care products, such as shampoo and liquid soap.
For example, if a product is too thick, problems may arise with pumping and packaging; too thin, and it may run straight through the consumer’s hands. Getting the rheology just right can be challenging from a manufacturing perspective, but is central to the product’s success
In the manufacture of these products, conventional rheometry testing typically takes place off-line, with sampling required from the process stream. This can take approximately ten minutes (depending on the number of measurement points required), not including the time needed to obtain the sample, send it to a QC lab and conduct internal checks.
Once analysed, if the product does not meet specif
