Coating solutions of trivalent chromium for coating zinc and cadmium
surfaces
    1.
    发明授权
    Coating solutions of trivalent chromium for coating zinc and cadmium surfaces 失效
    用于镀锌和镉表面的三价铬涂层溶液

    公开(公告)号:US4263059A

    公开(公告)日:1981-04-21

    申请号:US106093

    申请日:1979-12-21

    IPC分类号: C23C22/37 C23C22/34 C23F7/26

    摘要: Aqueous acidic chromate coating solutions are described for treating zinc, zinc alloy, or cadmium surfaces comprising trivalent chromium as substantially the only chromium ion present, fluoride ion and an acid, the trivalent chromium ions comprising a mixture of green and blue trivalent chromium. One method of preparing the green trivalent chromium is by reducing an aqueous solution of hexavalent chromium with sufficient reducing agent to reduce all of the hexavalent chromium to trivalent chromium. The blue trivalent chromium can be prepared by reducing hexavalent chromium with reducing agent and adding an acid and fluoride ion (pH

    摘要翻译: 描述了用于处理锌,锌合金或镉表面的酸性铬酸盐涂层溶液,所述锌,锌合金或镉表面包含三价铬,基本上仅存在的铬离子,氟离子和酸,三价铬离子包含绿色和蓝色三价铬的混合物。 制备绿色三价铬的一种方法是用足够的还原剂还原六价铬的水溶液以将所有六价铬还原为三价铬。 蓝色三价铬可以通过用还原剂还原六价铬并加入酸和氟离子(pH <1)来制备。 通过使所述表面与本发明的酸性水溶液接触来制备锌,锌合金和镉表面上的铬酸盐涂层。