Image forming apparatus configured to apply a transfer bias to a transfer nip based on a plurality of transfer conditions, image forming method, and recording medium

An image forming method, comprising:

• generating a plurality of transfer conditions for a transfer bias to be applied from a power supply device to a transfer nip between an image bearer to bear a toner image and a transfer member, the plurality of transfer conditions being different from each other and including a combination of values of at least a DC component out of the DC component and an AC component;
• switching the plurality of transfer conditions to apply the transfer bias from the power supply device to the transfer nip;
• and
• transferring an image from the image bearer to a recording material for each one of the plurality of transfer conditions to be applied, according to an adjustment mode that is set among a plurality of adjustment modes for adjusting the transfer bias corresponding to the recording material, wherein the plurality of adjustment modes include a first adjustment mode of switching the plurality of transfer conditions within each recording material of a plurality of recording material and a second adjustment mode of switching the plurality of transfer conditions for each recording material of the plurality of recording material.

A non-transitory recording medium storing program code for causing a computer to execute:

• generating a plurality of transfer conditions for a transfer bias to be applied from a power supply device to a transfer nip between an image bearer to bear a toner image and a transfer member, the plurality of transfer conditions being different from each other and including a combination of values of at least a DC component out of the DC component and an AC component;
• switching the plurality of transfer conditions to apply the transfer bias from the power supply device to the transfer nip;
• and
• transferring an image from the image bearer to a recording material for each one of the plurality of transfer conditions to be applied, according to an adjustment mode that is set among a plurality of adjustment modes for adjusting the transfer bias corresponding to the recording material, wherein the plurality of adjustment modes include a first adjustment mode of switching the plurality of transfer conditions within each recording material of a plurality of recording material and a second adjustment mode of switching the plurality of transfer conditions for each recording material of the plurality of recording material.