Abstract: A process for making a polyamide substrate characterized by enhanced breaking strength and fade resistance is disclosed. The process features the steps of treating a polyamide substrate, preferably a nylon 6 substrate having a hindered amine light stabilizer chemically bound thereto, with an effective amount of an ultraviolet inhibitor, an antioxidant and optionally, a dye, in the presence of a swelling agent for the polyamide that is also a solvent for the ultraviolet inhibitor and the antioxidant to impart high breaking strength to the substrate. A life preserver or other type of buoyancy device may be made from the process. A polyamide fabric comprising a dye, an ultraviolet inhibitor and an antioxidant also is disclosed. When a polyamide fiber of the present invention is exposed to sunlight, the useful life of the fiber is greatly increased compared to untreated polyamide fiber.

Abstract: A process for making a polyamide substrate characterized by enhanced breaking strength and fade resistance is disclosed. The process features the steps of treating a polyamide substrate, preferably a nylon 6 substrate having a hindered amine light stabilizer chemically bound thereto, with an effective amount of an ultraviolet inhibitor, an antioxidant and optionally, a dye, in the presence of a swelling agent for the polyamide that is also a solvent for the ultraviolet inhibitor and the antioxidant to impart high breaking strength to the substrate. A life preserver or other type of buoyancy device may be made from the process. A polyamide fabric comprising a dye, an ultraviolet inhibitor and an antioxidant also is disclosed. When a polyamide fiber of the present invention is exposed to sunlight, the useful life of the fiber is greatly increased compared to untreated polyamide fiber.