What enhancement was found in the fourth generation of nylon fiber development?

The fourth generation of nylon fiber development introduced significant improvements in water and solvent resistance. This enhancement is crucial because it contributes to the overall performance of carpets in environments where spills and moisture are common. By developing nylon fibers that repel water and resist the damaging effects of solvents, manufacturers created products that are more durable and easier to clean. This advancement allows carpets to maintain their aesthetic and functional qualities over time, reducing the incidence of stains and extending the carpet's lifespan.

While other generations of nylon might have focused on improvements in stain resistance, durability, or static reduction, the defining characteristic of the fourth generation specifically targeted the interaction of the fiber with liquids—an essential factor in maintaining the integrity and appearance of carpet flooring in residential and commercial settings.