A method for applying a bonding agent for supplemental ink includes, with a control system of a printing apparatus, determining regions of an image corresponding to regions where a supplemental ink is to be printed, and with the control system, adding an amount of pixels of a standard color channel to portions of a bitmap representing the image, the portions corresponding to the regions where the supplemental ink is to be printed. The amount of pixels is sufficient to trigger application of a bonding agent at the regions.