| Abstract: | A comparison of three different detergents was made by evaluating their properties of soil removal, soil redeposition and calcium carbonate deposition. The detergents included a phosphate granular detergent, a non-phosphate, carbonate built granular detergent and an unbuilt liquid detergent. The local water conditions were moderately hard and clay type soils were used. Detergency was evaluated on the basis of both visual and instrumental colour changes. In effecting soil removal, clay stained fabrics laundered with the phosphate detergent retained only a small amount of soil, while fabrics laundered with the two non-phosphate detergents showed heavier staining. In preventing soil redeposition, the phosphate detergent produced almost no visible redeposition; the unbuilt and carbonate built detergents ranked correspondingly lower. In assessing calcium carbonate deposition, the phosphate and unbuilt detergents showed little or no change, while the carbonate detergent continued to build up deposits with laundering. In summary, the phosphate detergent ranked highest in overall performance, with correspondingly lesser performance from the unbuilt and carbonate detergents. |
