Beschreibung:
<jats:title>Abstract</jats:title><jats:p>Calcium carbonate deposition on cotton fabric from soda ash‐based detergents containing polycarboxylates is measured and related to polymer composition and molecular weight, under varying conditions of temperature, water hardness and detergent composition. Deposition effects on fabric are compared with threshold inhibition effects and calcium binding capacities of the polymers.</jats:p><jats:p>Polyacrylic acids with molecular weights of 2000–5000 are most effective in preventing calcium carbonate deposition on fabric. A 1.5:1 acrylic acid:maleic acid copolymer is more effective than polyacrylic acid. Detergents with LAS left somewhat higher calcium carbonate deposits than detergents with a nonionic surfactant.</jats:p><jats:p>Prevention of visible calcium carbonate precipitation in the absence of fabric (“threshold effects”) appears at polymer levels considerably lower than those necessary to prevent calcium carbonate deposition on fabric. Deposition on fabric can be prevented at levels of polymer much less than that necessary to bind most of the calcium ions, as determined by the calcium binding capacity.</jats:p>