Sivelisa iintlobo ezininzi ze-OBA, i-agent emhlophe ye-fluorescent. I-Optical Brightener Agent BBU, ekwabizwa ngokuba yi-fluorescent whitening agent BBU, yikhompawundi yekhemikhali esetyenziswa kumashishini ahlukeneyo afana nelaphu, iphepha, kunye neeplastiki ukunyusa ukuqaqamba kunye nobumhlophe beemveliso.