Details about boraxsodium tetraboratedisodium tetraborateborate99.9% pure boraxsodium tetraboratedisodium tetraborateborate99.9% pure item information Increases the stain-removal ability of your detergent: pre-soak your laundry for 30 minutes in a solution of a tablespoon of borax per gallon of warm water or a 1/2 cup of borax in the washer in a pre-soak cycle. the alkaline ph of borax helps break down acidic stains, such as tomato or mustard. it works on grease and o il stains as well. Borax chemically called sodium tetraborate decahydrate. utility wise borax classified as a laundry booster for cleaning, and as a fungicide, preservative, insecticide (ants, fleas etc), disinfectant, desiccant and water softener. Borax is an important boron compound, a mineral, and a salt of boric acid with a powdery white appearance. “borax” may refer to similar compounds, distinguished by their water content including: borax pentahydrate (na 2 b 4 o 7 · 5 h 2 o); anhydrous borax or sodium tetraborate (na 2 b 4 o 7); borax decahydrate (na 2 b 4 o 7 · 1 0h 2 o).