Abstract: A tile for forming a floor covering includes a perimeter support wall, a top surface, interconnecting structure for releasably connecting with adjacent tiles, and intermediate upstanding grid structure. The intermediate upstanding grid structure comprises a repeating pattern of polygonal units, such as hexagons, having sidewalls extending from a bottom of the tile to the underside of the top surface. An arched support structure is disposed within each polygonal unit, connecting an upper portion of the sidewalls of each polygonal unit with the underside of the top surface. The arched configuration reduces stress concentrations at the junction of the arched support structure and the sidewalls.

Abstract: A system for applying a polyurethane coating to a polyolefin floor tile, comprising a conveyor for moving the floor tile past a plurality of treatment devices, including a solvent applicator, a heater, a plasma generator, an applicator, and an ultraviolet light system. The solvent applicator enables the polymer surface to be more responsive to the processes applied by the heater and plasma generator, increasing the energy of the top surface of the floor tile in preparation for the applicator to apply a liquid polyurethane to the top surface while in the energized state. The ultraviolet light system then exposes the polyurethane to ultraviolet light to at least partially cure it.