This paper describes a new method for rendering printed pieces realistically on a monitor based on the spectral reflectance data. The reflected light is modeled with the Extended Phong Model which is defined as an extension of the Phong Model in computer graphics.We apply the extended model to displaying the primary and secondary solid ink colors and their gradations. We propose an new interpolation method of the specular and body reflectance components in the reflection model. We show the results simulated on a monitor by the proposed method and compare these with the measured results.