Sodium tetraborate (Sodium tetraborate, borax, borax, borax, E285) ndi mchere wofooka wa boric acid ndi maziko amphamvu, odziwika bwino a boron, ali ndi ma crystal hydrates angapo. Chemical formula Na2B4O7.
Sodium tetraborate imagwiritsidwa ntchito ngati chigawo cha zotsukira ndi zodzoladzola; m'makampani opanga mapepala ndi mankhwala; kupanga ma enamel, glazes, magalasi owoneka ndi amitundu; monga mankhwala ophera tizilombo toyambitsa matenda komanso kuteteza.