Image forming apparatus and image forming method in controlling electronic resistance values for image transfer

An image forming apparatus, comprising:

• an image forming part having a transfer part including
• a transfer member, and
• a rotation member arranged so as to face the transfer member, and the transfer part being configured to transfer a developer with a transfer voltage to a recording medium of which a front surface is composed with a transfer region and a non-transfer region arranged between the transfer member and the rotation member, in the transfer target region where the developer is to be disposed and in the non-transfer region where the developer is not to be disposed;
• a measuring part that measures a first electric resistance value and a second electric resistance value,
• the first electric resistance value being defined as a resistance value between the transfer member and the rotation member in a state in which the transfer region of the recording medium is not present between the transfer member and the rotation member, and
• the second electric resistance value being defined as another resistance value between the transfer member and the rotation member in another state in which the transfer region of the recording medium is present between the transfer member and the rotation member;
• and
• a control part that determines the transfer voltage value in the transfer part based on the first electric resistance value and the second electric resistance value,
• the measuring part measures the first electric resistance value before the transfer part starts transferring the developer to the recording medium,
• the measuring part further measures a third electric resistance value that is defined as another resistance value between the transfer member and the rotation member in another state in which the transfer region of the recording medium is present between the transfer member and the rotation member,
• the second electric resistance value is measured after the third electric resistance value is measured, and
• the control part takes the third electric resistance value into account to determine the transfer voltage value.