| 摘要 |
<p>A water hardness controlling agent includes a polyacrylic acid or salt thereof having a molecular weight of between about 1,000 and about 50,000 g/mol, an acrylic-maleic acid copolymer or salt thereof having a molecular weight of between about 1,000 and about 100,000 g/mol and a phosphonocarboxylic acid or salt thereof. A ratio of acrylic-maleic acid copolymer or salt thereof to polyacrylic acid or salt thereof to phosphonocarboxylic acid or salt thereof in parts per million is about 1-30:10-80:6-20.</p> |
