Alcantara is a synthetic material produced by an Italian-Japanese joint venture — Toray and the ENI group — founded in the early Seventies. It is not suede, it is not sueded leather: it is a microfiber made of polyester and polyurethane, whose internal structure mimics the weave of natural suede with fibers less than a micron in diameter. The difference from leather is substantial: Alcantara does not have a heterogeneous structure, it has no grain, it has no tanning defects. It is uniform by definition.
In watchmaking, the material appears in three distinct contexts, and it is worth keeping them separate. The first is watch cases and watch holders: here Alcantara lines cushions, bottoms and interior walls because it is soft enough not to scratch polished surfaces, stable enough not to shed fibers and compact enough to absorb light impacts. Bennett Winch watch rolls or Charles Simon Spence cushions are classic examples. The second context is that of travel pillows or display stands like the Timenest Nest: there the Alcantara lining distributes pressure on the bracelet, preserving its shape over time. The third context — the most visible — is its use as a covering material on straps, often combined with rubber or leather, as happens in the HYT Hastroid inserts or in Armin Strom's proposals.
From the workshop I see some things that the notes do not say. Alcantara breathes reasonably well, better than varnished leather, but does not handle prolonged sweat well: it compresses, loses its hand, and seams fail before the surface does. On a watch holder or display stand this is not a problem; on a strap worn all day in summer, it is. The material cleans well with a damp, slightly alkaline cloth, but does not tolerate solvents. In terms of color it holds dye excellently — the green versions of the Armin Strom Tribute 1 or the blue of the HYT Supernova Blue Moon Runner confirm this — and does not fade in the light like some surface-dyed leathers.
One thing I am not certain about: whether there are significant performance differences between different suppliers of similar synthetic microfiber (Dinamica, Ultrasuede, anonymous products) and branded Alcantara. The name is registered and production is centralized at the plant in Nera Montoro, Umbria, but whether the chemical formula is truly exclusive or simply protected by the brand, I have no basis to state with certainty.