| 摘要 |
<p>1507531 Dyeing leather SANDOZ Ltd 12 May 1975 [14 May 1974] 19780/75 Heading D1B [Also in Division C3] Freshly tanned and neutralised full grained chrome leather is dyed by drumming in an aqueous liquor comprising an anionic azoic dyestuff, prepared by reacting diazotised 4- amino-4'-nitrodiphenylamine-2'-sulphonic acid with a condensation product prepared from salicylic acid and paraformaldehyde, followed by a treatment in the same bath with an anionic fat liquor based on sulphonated train oil. Calf suede leather is dyed by first drumming in aqueous ammonia and then dyeing with a liquor consisting of water, ammonia and the above dye, and adding formic acid to exhaust the dyebath. Chrome-vegetable tanned lamb leather is dyed by drumming in a liquor of water, the above dye and an anionic sperm oil emulsion and fixing the dyestuff on the leather by addition of formic acid.</p> |
