The use of Profilometry to Characterise the Leather Surface

The quality of the finished leathers is often determined based on the grain characteristics or pattern. The grain characteristics of leathers vary according to the age of the animal, breed, gender, climate, animal husbandry practices and processing conditions. However, the assessment of the leather surface or grain characteristics is often very subjective. In this study, the grain characteristics were determined using a profilometry technique. Profilometry, a metrological method, is essentially the measurement or assessment of surface texture and is linked to its friction and wear properties. The aim of the study was to define and grade the leather surface based on a given scale as well as to analyse the effect of various leather making operations, including tanning, on the grain texture of leather of species from different origins. Hides (bovine) and skins (goat) were subjected to various processing conditions, including extreme conditions, such as extended liming processes and shrunken grain tannage. The surface topography of the grain surface of the manufactured leather was analysed using a Zeta optical profilometer. A scanning electron microscopy was also used to observe the grain characteristics of the produced leather to verify the 3-dimensional stitched scans produced by the profilometer. The results showed a technique that can be used in forensic, quality control and research contexts to provide tanners an indication of the impact of their processing on the grain pattern of their leather. Key words: profilometry, grain characteristics, surface profile, texture.