Abstract: An identification label is affixed on a top surface of an image forming unit which is detachably installed in a main component of an image forming apparatus. The identification label is made of a thermosensitive paper on which a trademark logo is printed. A logo reader in the main component reads a pattern of the logo mark on the identification label. A control unit compares the read logo pattern with a previously stored pattern to discriminate whether the read logo mark is genuine or not. If the identification label has the genuine logo mark, the control unit executes printing. If the identification label has an irregular logo mark, printing is abandoned and an error message is displayed. When a genuine image forming unit is exhausted, the control unit controls a heating device to apply heat to the identification label in order to wholly or partially discolor the identification label so that the logo mark is transformed to unreadable one. That unit will be regarded as an irregular one thereafter.

Abstract: Three ink storage chambers stored into a main body case of an ink cartridge is isolated from four surfaces of this main case body by way of a partition and depressing partition portions projected from this portion. Also, these ink storage chambers are isolated from a bottom portion of the main body case by a stepped portion of a lower cylindrical portion, and is arranged by forming space between a lid and the own ink chambers. Only refilling hole portions of an upper cylindrical portion are communicated with an external portion via holes of the lid. A label on which a trademark “ABC” is printed is attached onto the upper portions of the three refilling hole portions. A label reading apparatus is provided on the side of an ink-jet printer, and a printing operation by any ink cartridge other than the genuine-labeled in cartridge is not carried out. As a genuine ink refilling member, at least ink bottles and a label are employed as a set of such a genuine ink refilling member.