US Patent 7454813 Cleaning device and method

A cleaning device includes a soft sponge layer, having at least one rib or bead on its surface; an intermediate layer, which is harder than the sponge layer, a cloth layer, that is bonded to the intermediate layer, opposite to the sponge layer. The layers may be bonded to one another. Bonding the soft sponge layer to a harder intermediate layer already considerable improves upon the handling achieved by the sponge with the rib. Even when the sponge is completely soaked with the cleaning agent it remains stable in shape due to its firm bonding to the harder intermediate layer. The user may grasp the hard intermediate layer of the device so that the sponge will not be compressed.