Borax in soap making
If you have been into soap making for any length of time, you have probably at least heard about adding borax or sodium tetraborate decahydrate to soap recipes. The three main applications in soap making are: water softening, pH buffing, and as a deodorizer. Although borax does show a tendency to be toxic especially when ingested, the amounts used in soap recipes are quite small. Although, personally neither me or my family have not experienced adverse skin reactions, I suggest you only use borax in laundry and home cleaning soap cleaning until you can determine if you can use borax in your personal care soaps. If you want to see a recipe for a hard laundry prewash soap bar that rivals or trumps ZOTE or any other commercial laundry bar, try link below for a good all vegetable solution to the toughest stains on your clothing.
The water softening properties are based on borax’s ability to cause the hardness ions calcium and magnesium to form powdery insoluble solids that can easily be rinsed away. This is a two fold benefit to any soap recipe. First you have the calcium ions and magnesium ions sequestered allowing the soap to reach its full lather. Secondly, the insoluble powdery solids being easily rinsed away will not leave a deposit on your fabrics caused by the soap reaction with calcium and magnesium ions forming a dinghy scum on your fabrics.
Borax because of its mild alkaline nature( pH of about 9) acts as a buffer in strongly alkaline soap recipes. This is important when you have a 0% potassium or sodium hydroxide discount which is needed when making liquid soaps or cleaning agents. For the laundry bar, this makes hand washing difficult garments easier on the hands as there is no unreacted alkali in the finished product. Also if you are making potassium based liquid soap borax is almost essential to neutralize potassium hydroxide as liquid soaps are almost always made with a 0% alkali discount unlike most bar soaps.
Many commonly foul stenches in fabric are acidic in nature. Borax, like baking soda, has the property to absorb or eliminate foul odors. This is what makes this recipe stand out above Zote and all the rest in cleaning ability. Not to mention an oil blend which is effective and very cost effective enabling you to make this soap at a cost of $0.75 a bar or less depending.