New Measures of Whiteness That Correlate with Perceived Color Appearance

Most whiteness formulas currently in use satisfactorily characterize the appearance of commercial whiteness. However, when these formulas are applied to colored samples they are generally unsuccessful in assessing tinted samples with chromaticities placed on the borders of white colors. In this study, new formulas expressing whiteness are proposed. These are compared with CIE, Hunter and Ganz whiteness formulas and TAPPI brightness, through perceptual evaluation and instrumental measurements and analyses. Both of the proposed whiteness formulas matched well with 48 randomly selected observer assessments for printed samples, the one that is based on a maximum at neutral white being in a lesser degree. On the other hand, CIE, Hunter and Ganz whiteness formulas had a poorer correlation with the observers’ evaluation. TAPPI brightness also agreed well with the observers’ assessments, but it cannot be strictly correct because of its reliance on a narrow wavelength range. Relatively saturated chroma values are associated with the maximum whitenesses with the evaluated CIE, Hunter and Ganz whiteness formulas. The proposed whiteness formulas don’t suffer from this abnormality. * Corresponding author. Tel.: (334) 466-2028 E-mail address: [email protected]