| 摘要 |
1365816 Purifying nickel plating baths KEWANEE OIL CO 28 Jan 1972 [16 Feb 1971] 4209/72 Heading C7B An acid Ni plating bath containing as additive coumarin or derivative thereof is purified to remove the conversion product hydrocoumaric acid (2 hydroxyphenyl propionic acid) or derivative thereof formed during plating by contacting at least part of the bath with a porous hydrophobic resin e.g. a copolymer comprising a major amount of polystyrene and a minor amount of divinylbenzene. The bath may be flowed through a packed bed or column of the resin, or through two columns in series. The conversion product may be removed from the polymer by washing with an aqueous alkaline solution e.g. of Na 2 CO 3 , NaHCO 3 , K 2 CO 3 , NaBO 2 , KOH, NaOH or NH 4 OH; the additive may be removed from the polymer by washing with a solvent e.g. alcohol, ketone, ether, glycol, ester or hydrocarbon. |
