has paper feeding trays 111 112 and 113 in three stages where sheets of printing papers 121 122 and 123 are set respectively for instance the printing papers 121 and 122 may be sheets of plain paper and the printing paper 123 may be sheets of printing paper with electronic tags 33 attached thereto corresponding to those paper feeding trays 111 112 and 113 paper feeding rollers 131 132 and 133 are arranged respectively and corresponding to the paper feeding rollers 131 132 and 133 conveyance rollers 141 142 and 143 are arranged respectively by this structure the printing papers 121 122 and 123 can be fed to an printing unit 20 via the paper feeding rollers 131 132 and 133 and then via the conveyance rollers 141 142 and 143 respectively in the printing unit 20 i e a print engine in this embodiment a surface of a photoconductive drum 21 is to be charged evenly by a charging roller 22 the charges on the photoconductive drum 21 will be eliminated selectively by a laser beam lb to form an electrostatic latent image after which toner will be transferred to the charged part of the photoconductive drum 21 by a developer 23 to develop the electrostatic latent image a registration roller 24 functions to once stop the paper feeding of the printing paper being fed from the conveyance roller 143 and resume the paper feeding at predetermined timing to feed the printing paper between an electrostatic transferring roller 25 and the photoconductive drum 21 the electrostatic transferring roller 25 functions to make the toner image on the photoconductive drum 21 be transferred on the printing paper being fed through.