Builders

Builders are compounds used to adjust certain physical or chemical properties of final products (typically in detergent formulations). These products have some value to soapers as they may be be used to produce soaps which possess better specific properties than simple soaps. In particular, many builders fall into the "water softener" class of compounds which possess the ability to bind heavy and alkali (class 2) metal ions which typically form "scum" during soap manufacture and use.

In practical terms for soapers builders are basically divided into :

Phosphates - Typically Sodium Tripolyphosphate (STPP), Trisodium Phosphate (TSP), Tetrapotassiumpyrophosphate (TKPP)

Phosphates are a class of compounds commonly used to improve the efficiency of soap as a cleaning compound by reducing the formation of insoluble soaps ("scum") and dirt redeposition. Usage is normally low (less than 5% w/w in the final product). They are used to particular advantage in liquid soaps where cloudiness is commonly encountered due to formation of insoluble salts - as little as 1% STPP or TKPP can help clear the soap. They may also be used to advantage in bath salts where their ability to bind heavy metals give more "foam" in bath salts built on natural soaps.

STPP - Sodium Tripolyphosphate

TKPP - Tetrapotassium Pyrophosphate

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