Dyes for fibres containing amino groups

摘要

Dyes which contain sulphonic acid, hydroxyl and/or sulphonamide groups are blocked cationically by the fixation of weak or strong cationic compounds. - The dyes are used on fibres which contain amino groups, particularly wool. Solution of the dye is easy and does not require an alkaline medium. Dyeings on wool have good resistance to rubbing. - To the dye, which after coupling, is in a slightly alkaline or slightly acid suspension, a weak or strong cationic compound is added followed by heating the mixture to is not > 60 deg.C, to form the addition compound. The dye is precipitated in finely-divided form by addition of an acid. Alternatively, if the dye has been isolated and dried after coupling, it is dissolved and the solution is treated as above.