Transfer device and image forming apparatus

A transfer device comprising:

• a toner image bearing member that bears a toner image thereon;
• a transfer section that transfers the toner image borne on the toner image bearing member onto a recording medium;
• and
• a bias applying section that applies a transfer bias voltage for transferring the toner image, the bias applying section applying a transfer bias voltage which an alternating voltage is superimposed on a direct current voltage,
• the alternating voltage having an alternating voltage waveform in which a transfer side potential to shift the toner image from the toner image bearing member to the recording medium and an opposite transfer side potential to shift the toner image from the recording medium to the toner image bearing member are applied so as to alternate with each other, and a first period in which a first peak-to-peak voltage is applied and a second period in which a second peak-to-peak voltage, lower than the first peak-to-peak voltage, is applied, are alternately repeated, and when f1 denotes a frequency of the first period and f2 denotes a frequency of the second period, f1=f2 is satisfied.