Synthesis and fluorescent investigations of VBL-based waterborne polyurethane dye

►A fluorescent brightener VBL-based waterborne polyurethane dye is synthesized. ► Absorption and emission maxima of the dye are blue shift about 16 and 11 nm. ► Fluorescence intensity of the dye is prominently enhanced comparing with VBL. ► Fluorescence of the dye is stable and is not sensitive to hydroquinone quencher.