Glossary · Labelling & formulation
How a product flows and deforms: viscosity, yield stress and shear thinning. Rheology decides how a product pours, pumps, spreads and holds suspended particles, and is tuned during prototyping.
Getting this right early shapes the formula, the label and the claims, and avoids costly reformulation once a product is close to launch.
Guires CSL formulation, testing, clinical and regulatory teams work with Rheology on client projects every week, from the first brief to the final product file.
PrototypingRelated terms
The standard ingredient names used on cosmetic labels in the EU, US, ASEAN and many other markets, assigned by the INCI committee of the Personal Care Products Council.
Read definition →The ISO guidelines on technical definitions and criteria for natural and organic cosmetic ingredients (Part 1, 2016) and the way to calculate natural and organic origin indexes for ingredients and products (Part 2, 2017).
Read definition →A measure of acidity or alkalinity on a scale of 0 to 14.
Read definition →A dispersion of oil and water held together by emulsifiers, either oil-in-water (most lotions and creams) or water-in-oil (richer, water-resistant textures).
Read definition →Regulations and standards are listed first, then peer-reviewed literature. Sources checked October 2026.
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Our formulation chemists, testing scientists and regulatory specialists work alongside your team, from the first brief to a market-ready product. Bring a brief, a benchmark or just an idea: a scientist will reply within one working day with next steps and an indicative scope.