Optical brightener CBS-X (OBA 351) C.I.:351 CAS No.: 27344-41-8 Appearance: Yellowish green crystal powder/granular Max. uv absorption wavelength: 348 nm 1% Extinction coefficient: 1140 Usage: A good whitening agent for lacquer, soap, printing ink and man-made fiber etc. Package: 25KG fiber drums with PE liner