US Patent 7543350 Apparatus for applying drywall compound to a surface

A lightweight tool for applying compound to drywall and like surfaces is achieved by using closed-cell foam to form an application layer secured to a stiff plate. A handle secures to the stiff plate to facilitate use. An application layer made of closed cell foam of substantially uniform thickness nonetheless provides a lower surface having contoured perimeter portions by conforming to a plate having upwardly sloping perimeter regions. In an alternative embodiment, perimeter portions of an upper surface of an application layer are formed to be downward sloping. The upper surface of the application layer may be secured to the lower surface of a plate. The downward sloping portions may be deformed upwardly to be flush with the plate, creating corresponding upwardly sloping portions on the lower surface of the application layer. In yet another embodiment, the application layer is formed or machined to have an upwardly sloping perimeter portion.