| 摘要 |
1,222,437. Bleaching textiles. DOW CHEMICAL CO. 16 April, 1968, No.17900/68. Heading D1P. Textile materials, e.g. cotton cloth, are bleached by treating them with an aqueous bleaching composition comprising metachloroperoxy benzoic acid, monoperoxyphthalic acid or peroxyacetic acid, a water soluble source of magnesium or calcium ions, e.g. calcium, nitrate or magnesium sulphate, and water, which has a pH of at least 9 and a peroxy acid concentration which provides an active oxygen concentration of 10-150 parts per million, with metachloroperoxybenzoic acid either calcium or magnesium ions being used at a metal ion to peroxy acid ratio of 0:5 .to 1.0, with monoperoxyphthalic acid magnesium ion being used at a metal ion to peroxyacid ratio of 0.5-2.5 and with peroxyacetic acid calcium ion being used at a metal ion to peroxyacid ratio of 0.5 to 1, the metal ion to peroxy acid ratio being based on moles of metal ion to acid equivalents of peroxyacid selected and the bleaching composition being adjusted to an alkaline # H by the addition of alkali of sufficient strength to bring the pH to at least 9, e.g. caustic soda. Bleaching may be effected to 100‹-150‹F. |
