Abstract: An ink jet printing method and apparatus using a color ink and a print performance improving ink which minimizes an image quality degradation due to blank lines formed by failed or faulty nozzles. This system enables the use of a print head even with failed or faulty nozzles by minimizing the image quality degradation and extends the life of the print head before replacement. The print performance improving ink is deliberately ejected onto a blank line or its vicinity to produce the so-called primer effect, thereby inducing the color ink dots on the lines adjoining the non-ejecting nozzle line to spread into the blank line to make the blank line undistinguishable.