Abstract: A marking device includes an ink jet printer (6) using an on-demand system. The printer (6) includes a body (18), a head (22), a slide table (24), a tray (26), an ink vessel (28), a solvent vessel (30), a pump (32) and a rest (34). The head (22) has a nozzle. The shortest distance between the tip of the nozzle and a golf ball (46) set into the tray (26) is equal to or greater than 0.2 mm. The ink vessel (28) is filled with an oil-based ink or an ultraviolet setting type ink. The ink is fed to the head (22) through a tube (48). The ink is discharged from the nozzle and is then moved to the surface of the golf ball (46). The solvent is supplied from the solvent vessel (30) toward the rest (34) through a tube (50) and the pump (32). When the printer (6) is stopped, the nozzle is immersed in the solvent of the rest (34).

Abstract: A packaging box, for a golf ball, is formed by folding a packaging sheet comprising a decomposable laminate material consisting of a polylactic acid-containing polymer film and a sheet of paper laminated with the polylactic acid-containing polymer film. A portion corresponding to a window is cut out from the paper, and the window is covered with the polylactic acid-containing polymer film laminated on the paper. The window is formed straddlingly on two or three planes such that the polylactic acid-containing polymer film covering the window is bent perpendicularly at a boundary between the planes adjacent to each other. A raised portion is formed on the packaging sheet.