Improved dyeing processes for yarn and fabric materials are described. Dye pattern definition on a textile material is enhanced by treating the fabric or the fibers from which it is made with a quaternary ammonium compound and by including in the dye composition a gum which will react with the quaternary ammonium compound to form a viscous gel. The gel minimizes migration of the dye prior to fixation of the dye, and therefore pattern definition is improved. Similar improvements can be obtained when space dyeing yarn that comprises fibers that have been so treated.