PURPOSE: To provide an elapsed-time indicating body which can indicate elapsed time in accordance with an optical density which largely changes within such a wide range of time as several hours to several months even at a room temperature, does not spoil the clothes, etc., and does not conceal characters, etc., printed on a substrate even when the body becomes discolored. ;CONSTITUTION: An elapsed-time indicating body is constituted by forming a discoloring agent containing layer 2 containing a discoloring agent which can discolor a color former in a color developing state on a color former containing layer 1 containing the color former in a color developing state. Or, a color developing member composed of a color former containing layer 1 containing the color former in a color developing state on a substrate and a discoloring member composed of a discoloring agent containing layer 2 containing the discoloring agent which can discolor the color former in a color developing state are constituted in separate members.;COPYRIGHT: (C)1995,JPO
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