| 摘要 |
<p>Copper sulphate crystals are dissolved in distilled water, hydroxyethyl cellulose added and the mixt. allowed to stand for around two hours. A second mixt. is prepd. from copper purpurin, formic acid, sulphuric acid and ethyl alcohol. The two mixts. are combined and shaken, leaving the paint ready for use after a rest period.</p> |
