An image forming apparatus for reproducing a black color by using an ink other than a black ink when recording an image on a recording medium is disclosed. The image forming apparatus includes an image processing part for disposing dots of multiple colors in various gradation levels, the image processing...http://www.google.com.au/patents/US7481510?utm_source=gb-gplus-sharePatent US7481510 - Image forming apparatus, image processing method, and printer driver
