Yellow is a printer ink because it provides the cleanest possible absorption of blue light while reflecting both red and green wavelengths. Among the three chromatic printing inks, yellow typically has the highest luminance reflectance and the sharpest absorption cutoff, meaning it creates minimal unwanted absorption in the green and red regions. This precision is crucial for creating bright oranges and greens when combined with magenta and cyan respectively.
Yellow is the most luminous of all printer inks, and the closest to a pure spectral color, appearing at wavelengths between 570-590 nanometers. The human eye is most sensitive to the brightness of yellow. Our light sensitivity to yellow stems from: stimulation of red and green cones, it’s wavelength in the most sensitive range, it has high energy compared to other color’s wavelengths. Yellow is the brightest color.