The Latest at TRI

Dr Trefor Evans, Institute Fellow and Director of Research, has published another, in a long line, of his famous articles on hair claims substantiation in Cosmetics & Toiletries Magazine. This time Trefor focuses on hair softness.

The North American hair conditioner market is expected to reach $3.1 billion by 2023. Furthermore, hair conditioners account for 53% of the whole US hair care market. Despite this, one of the key end-benefits associated with hair conditioners, hair softness, has still not properly been characterized. In this article Trefor takes the reader through the latest developments in testing the flexibility of hair, including single fibre bending and torsion experiments. He also explains how hair water content and some formulation ingredients can affect fibre stiffness. In end, however, he explains that hair surface friction may be one of the main drivers for consumer perception of hair softness. Clearly, there is still much more to learn about this very important and illusive attribute. Please contact Trefor if you are interested in hair softness claims (


T.A. Evans, A Soft Touch. Concepts in Hair Softness, Cosmetics & Toiletries, Vol. 134(10), 46-53, Nov/Dec (2019)

Dr Paul Cornwell, Director Business Development, and Dr Ernesta Malinauskyte, Principle Research Scientist in Hair Care Research, have pulled together a new review on hair breakage in Afro-textured hair. This follows-on from an article last year on ethnic hair care from Dr Trefor Evans, Institute Fellow and Director of Research.

An Afro-textured hair fibre with a longitudinal crack forming.

Afro-textured hair, known for its tight curls, is well-known to be prone to breakage; chemically straightened Afro-textured hair even more so. As a result, hair breakage is one of the top concerns of consumers with this hair type. The question being asked at TRI is: why is Afro-textured hair so fragile? In this review article, Paul and Ernesta work through all the evidence in the literature that might explain what is happening. Is it related to the shape of the hair, or composition of the hair, or the inner structure of the hair? The conclusion, at this stage, is that tight curls increase tangling. The shape also creates internal stresses when the hair is unbent, untwisted or stretched. The uneven internal structure of the hair further adds to the problems. More work is being done by Paul, Ernesta and Trefor in the TRI Textured Hair programme to explore things further and to design solutions. If you are interested in supporting our Afro-textured hair research programme please contact Paul (


Cornwell, P. and Malinauskyte, E. Defying Damage: Understanding Breakage in Afro-textured Hair. Cosmetics & Toiletries Magazine, February, 21-29 (2020) T.A. Evans, New Focus for Ethnic Hair, Cosmetics & Toiletries Magazine, Vol. 134(6), June, 35-41 (2019)

Dr Samuel Gourion-Arsiquaud, Director Skin & Biosubstrates, has, together with Iris Rubin MD, the founder of SEEN Hair Care, been investigating what gets left behind on your skin after you use hair products.

Remains of hair shampoo and conditioner on scalp skin cells removed by tape-stripping .

Have you ever wondered what gets left behind on your scalp, face and back after you have used a hair product? This may be more than of academic interest. Dermatologists believe that product deposits may have an important role in the development of conditions such as scalp acne. Using the advanced spectroscopy tools available at TRI, Samuel, and his team, were able to detect the remains of hair products on the skin surface. Results showed that rinse-off products are not completely removed by washing. In addition, the presence of residues from leave-on products on the skin increases with time as product is transferred from the hair. Further work is needed now to investigate the effects of these hidden remains on scalp condition. For more information, and a copy of the full article contact Samuel (


Rubin, I.K. and Gourion-Arsiquaud, S. Deposition and Retention of Hair Care Product Residue Over Time on Specific Skin Areas. Journal of Drugs in Dermatology 119 (2020)

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