Abstract: A coaster type device of cup design that will seal on the vertical side of a can and or container, here forth “can”, made of a potentially corrosion prone material that may cause unwanted marks on a surface the can could be placed. The device would be manually applied to the can and would stay on the can due to mechanical interface and frictional fit between the seal area and the vertical side of the can. The seal on the can and the solid physical coaster would produced a contained volume of the can base from the sealed surface down blocking any unwanted transfer from the can to the surface it would be placed.

Abstract: Inks are disclosed wherein the ordinary mixed light color of the ink is a color substantially different than the fluorescent color of the ink. Methods of use include detection of at least the fluorescent wavelength of the ink or detection of both the ink colors when irradiated for fluorescence and by exposure to mixed light.