| 摘要 |
1,233,488. Ion-exchange. ECONOMICS LABORATORY Inc. 8 Oct., 1969 [18 Oct., 1968], No. 49421/69. Heading B1J. [Also in Division A4] A dishwashing system comprises in combination a dishwashing machine and water treatment means including a weakly acidic cation exchange resin in the hydrogen form and means for passing water which may be hot, from the water treatment means to at least one stage in the cycle of operations of the machine. Weakly acidic cation exchange resins are considered to have a pKa value greater than 4.0 and are exemplified by polyacrylic acid crosslinked with divinylbenzene (pka=5.3). |
