Two of the greatest challenges yarn materials face when used for outdoor furniture are color fastness when exposed to sunlight, and deterioration from moisture when exposed to outdoor environments.
To meet these challenges, some of the most suitable outdoor yarns are nylon, polyester (PET), and PP dope dyed yarns. They offer excellent color fastness, and their hydrophobic properties make them resistant to moisture deterioration, which is seen as the best yarn for outdoor use.