Sentence:  In the household market , there are also low-sudsing detergent formulations based on nonionic actives with about the same amount of phosphate <WSD>builder</WSD> ; light-duty synthetic detergents with much less builder ; and the dwindling built soap powders as well as soap flakes and granules , none of which are now nationally advertised . 
Meaning of the word marked with <WSD> tags:  a substance added to soaps or detergents to increase their cleansing action