As the quality index of white or near-white paper and paperboard, whiteness has always been valued by people in the paper industry. They are represented by the blue light diffuse reflectance factor of the continent sample. The calculation formula is:
W=B(1)
(1) In the formula, W is the whiteness of papermaking, and B is the blue color in the three-dimensional excitation value of the color.
The 510/2469 and 510/2470 standards promulgated by the 510 organization in 1979 made a statement on the spectral characteristics of the Whiteness Meter.
Unified regulations: the effective wavelength is 547nm ± 0.5nm, the half-wave width is 4nm, and ElrePh. The Whiteness Meter is designated as a reference instrument for international standards.
