Izibani ezikhanyayo zibizwa nangokuthi ama-optical brightening agents noma ama-fluorescent whitening agents. Lezi yizinhlanganisela zamakhemikhali ezimunca ukukhanya endaweni ye-ultraviolet spectrum kagesi; lezi ziphinde zikhiphe ukukhanya endaweni eluhlaza okwesibhakabhaka ngosizo lwe-fluorescence