Conventionally known inkjet printers include paper moving type inkjet printers and flatbed type inkjet printers. Paper moving type inkjet printers use ink heads that move in a primary scanning direction to print on media carried in an auxiliary scanning direction (perpendicular to the primary scanning direction) by a carrier device. Flatbed type inkjet printers use ink heads that move freely in the primary scanning direction and auxiliary scanning direction to print on the media. In these conventional inkjet printers, color inks of various colors are discharged from moving ink heads onto the media to perform color printing on the media.
In the color printing process using the inkjet printers described above, visible color inks, also called process color inks, such as cyan (C), magenta (M), yellow (Y) and black (K) which reflect light in their respective wavelength ranges, are generally used. The visible color inks in various colors are discharged from their individual ink heads for color printing to take place.
However, the brightness of the images printed in color using the visible color inks or process color inks is limited because of the limited brightness of the visible color inks. The problem lies in that the brightness of a combination of process colors cannot exceed a certain threshold. For example, even if a user feels that the brightness of an image is lacking upon viewing a finished piece of printed media, the brightness of the image beyond what is inherent in each of the visible color inks cannot be obtained.
As such, a color inkjet printer that can enhance the brightness of a printed color image is desired.