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Widely used in industries such as papermaking, textiles, plastics, paint, and chemicals. The main measurement of blue light diffuse reflectance coefficient (R457) is called blue light whiteness or ISO whiteness. R457 whiteness regulation uses an approximate A light source illumination, with the peak wavelength of its effective spectrum at 457nm.

 

Standard：GB/T 5950, 2913 ；ISO 2470