this time the intermediate transfer belt 161 and the transfer roller 110 are brought into contact with each other under pressure with a predetermined nip while a voltage high voltage with reversed polarity of the polarity u2212 of charged toner is applied to the transfer roller 110 for transferring of the toner onto a sheet in order to allow the transfer roller 110 to give the above stated nip steadily any one of the transfer roller 110 and the intermediate transfer belt driving roller 162 may be made of a hard material e g metal and the other may be an elastic roller made of a soft material e g elastic rubber roller or foaming resin roller as stated above toner adheres to the intermediate transfer belt 161 in contact with the photoreceptor drums 103 or toner may remain on the intermediate transfer belt 161 without being transferred to a sheet by the transfer roller 110 and such toner causes the mixture of colors of toner at a following step in order to avoid this the intermediate transfer belt cleaning unit 165 is provided to remove and collect such toner the intermediate transfer belt cleaning unit 165 includes a cleaning blade for example as cleaning member coming into contact with the intermediate transfer belt 161 at a portion of the intermediate transfer belt 161 brought into contact with the cleaning.