| 摘要 |
<p>Pickling bath comprises a mixture of aq. nitric acid and an organic liquid which is not miscible with water and non-reactive with aqueous nitric acid. Up to 0.75% wt. of at least one anionic surface active agent comprising at least one hydrophobic substituent containing C10 to C26 in an uninterrupted chain, at least 6% of sulphuric ester and 0.005 - 8% of at least one C12-26 unsaturated carboxylic fatty acid are incorporated. The surface active agent may be sulphonated castor oil, sulphonated peanut oil or sulphonated soya bean oil; the unsaturated fatty acid is selected from dodecanoic, linoleic, linolenic, myristoleic, palmitoleic, docosanoic and stearoleic acids. The bath is used for the pickling of zinc plates by dabbing the photoengraved surface of the latter with the mixture.</p> |
