into the used toner bottle 6 collector box 22 and an erasing lamp 23 the arrow of a dotted line shown in fig6 indicates the direction in which the beam of incident light reaches the photosensitive drum 17 the toner supply bottle 1 for supply of the toner to the developing device 20 is attached at the position indicated in fig6 it is repeated once again that the bottle 1 when emptied of its contents turns into the used toner bottle 6 now the second embodiment of this invention will be described below with reference to fig7 through 10 fig7 illustrates a toner supply bottle 101 as a second embodiment of this invention in a state ready for use as illustrated in fig7 the toner supply bottle 101 comprises a cap 102 a mouth 104 enclosing a tubular opening a bottle body 103 and a marginal portion 108 used for separation which functions as a form changing portion when the supply of toner is completed and the toner supply bottle 101 is emptied the marginal portion 108 used for separation from the bottle 101 is cut off as illustrated in fig8 to facilitate the separation the portion of the bottle body corresponding to the marginal portion 108 is formed with a small wall thickness at the time the bottle is molded when the cap 102 fitted around the mouth is powerfully turned the twist consequently exerted causes the marginal portion 108 used for separation formed with a small wall thickness to be sheared so that the bottle is separated into two parts as illustrated in fig8 otherwise the cutting of the marginal portion 108 used for separation may be.