摘要 |
A vapor process for mineral dyeing cotton textiles is disclosed. Cellulosic fabric is impregnated with a chromium solution, exposed to sulfur dioxide vapors, dried, cured, and washed. The result is a superior process to "pearl gray" mineral dye fabric. Chromium containing salts used in the pad bath are selected from the group consisting of (NH4)2Cr2O7; K2CrO4; (NH4)2CrO4, Na2CrO4; Na2Cr2O7; and K2Cr2O7. The pad baths contain from about 3.5% to 5.0% chromium consisting of 40 to 50 parts of a 20 to 28% sodium dichromate dihydrate solution made alkaline with 25 to 50 parts of 10 to 20% sodium hydroxide solution to attain a pH of about 9.6 to 13.0 with about 0.5 parts of wetting agent and 0-30 parts of water. A pad bath comprising about 3 parts of ammonium dichromate, 7.5 parts ammonium carbonate, 0.6 parts zirconyl ammonium carbonate and 0.5 parts wetting agent in about 90 parts water, reacted with about 40 parts concentrated ammonium hydroxide to result in a final pH of about 11, can also be used.
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