Woolmark notes that Merino naturally absorbs ultraviolet radiation, while fabric density and colour affect the protection achieved. Its UV-Control process adds an absorbing finish at suitable yarn, fabric or garment stages and fixes that treatment during drying. The aim is additional protection without losing the intended handle.

A UV-Absorbing Finish Adds Another Variable to Merino Protection

A fibre name alone is therefore not an adequate sun-protection rating. The finished textile needs information about its tested performance, and wear conditions can also matter. The treatment illustrates one engineering route, rather than making every Merino garment equivalent for exposure to sunlight.