Patent ID: 7672606

Claim:
A method for transfer voltage adjustment for use in an image forming apparatus in which a toner image formed on a toner image support is transferred to a transfer element with application of a transfer voltage, comprising the steps of: forming a first halftone reference pattern on the toner image support under a first toner image forming condition; transferring the first halftone reference pattern to the transfer element at the saturated density with application of a first saturated transfer voltage thereto; calculating a first amount of adhering toner of the first halftone reference pattern on the transfer element; forming a second halftone reference pattern on the toner image support under a second toner image forming condition; transferring the second halftone reference pattern to the transfer element at the saturated density with application of a second saturated transfer voltage thereto; calculating a second amount of adhering toner of the second halftone reference pattern on the transfer element; acquiring a saturated amount of adhering toner when a density-saturated reference pattern is transferred to the transfer element at the saturated density, from previously stored data; and setting up a saturated transfer voltage for realizing the saturated amount of adhering toner, based on the first saturated transfer voltage, the first amount of adhering toner, the second saturated transfer voltage, the second amount of adhering toner and the saturated amount of adhering toner.