Method of controlling color mixing on nozzle plate of inkjet printhead

Abstract

An inkjet printer includes a stationary inkjet printhead positioned relative to a media feed direction. The printhead includes a plurality of color planes for ejecting a plurality of different inks, each color plane having a row of nozzles and each nozzle in a respective color plane being supplied with a same ink. A first ink tank containing yellow ink is in fluid communication with a first color plane of the printhead and a second ink tank containing black ink is in fluid communication with a second color plane of the printhead. The first color plane is positioned furthest upstream in the printhead with respect to the media feed direction, and the second color plane neighbors the first color plane.

1 . A method of controlling movement of ink across a nozzle plate of an inkjet printhead, said nozzle plate having a color row of nozzles neighboring a black row of nozzles, the method comprising the steps of:
 supplying a color ink to the color row of nozzles and printing the color ink therefrom;   supplying black ink to the black row of nozzles and printing the black ink therefrom, wherein:   the black ink contains less surfactant than the color ink; and   any color ink flooded on the nozzle plate preferentially moves towards any black ink flooded on the nozzle plate.   
     
     
         2 . The method of  claim 1 , wherein the color ink is a cyan, magenta or yellow ink. 
     
     
         3 . The method of  claim 1 , wherein the color row of nozzles is positioned further upstream in the printhead relative to a paper feed direction. 
     
     
         4 . The method of  claim 3 , wherein the color ink is a yellow ink 
     
     
         5 . The method of  claim 1 , wherein a distance between the color and black rows of nozzles is less than 200 microns.