Stamping device

A stamping device 1 which can easily conceal personal information written or printed by stamping a pattern on a portion where the personal information is written or printed comprises a rectangular stamping block 7 whose lower surface 7a is made to function as a stamping surface, an ink absorbed mat which is impregnated with an ink and is superimposed on an upper surface of the stamping block, and a stamp main body having the stamping block and the ink absorbed mat, the stamping surface being pressed against a pattern transfer target object to thereby transfer a pattern of the stamping surface on to the pattern transfer target object, wherein the stamping surface comprises a pattern configuration which is formed by densely arranging characters (see Fig.3), figures or pictures, or straight lines and curved lines to thereby have spaces of small areas defined therebetween, whereby by stamping the pattern configured in the way described above on characters written or printed on a sheet of paper, the characters so written or printed can be concealed, thereby making it possible to realize the protection of personal information.