Process for dyeing of polymers of ethylene with basic dyes

A process for dyeing a polyolefin article, comprising the steps of:

• (A) contacting the polyolefin article with an aqueous dyebath, said aqueous dyebath having a pH of 5.0-7.5, a temperature of at least 35.degree. C. and containing basic dye in a concentration of at least 0.4 g/l, said polyolefin being a blend comprising (i) 65-99 parts by weight of a polyethylene selected from the group consisting of homopolymers of ethylene and copolymers of ethylene with C.sub.3 -C.sub.10 higher alpha-olefins, and mixtures thereof, and (ii) 1-35 parts by weight of a copolymer selected from the group consisting of direct copolymers and graft copolymers wherein (a) said direct copolymer is a copolymer of ethylene with at least one alpha,beta-ethylenically unsaturated monocarboxylic acid having from 3 to 8 carbon atoms, the acid moieties being randomly or non-randomly distributed in the polymer chain, the carboxylic acid content being 0.5-50% by weight of the direct copolymer, (b) said graft copolymer is obtained by grafting 0.1 to 20 percent by weight of at least one alpha,beta-unsaturated carboxylic acid having 3 to 8 carbon atoms or unsaturated carboxylic acid anhydride onto a preformed polyolefin backbone derived from ethylene or ethylene and C.sub.3 to C.sub.8 alpha-olefin, and (c) said copolymer is a copolymer of (a) or (b) in the form of a zinc ionomer,
• (B) maintaining said polyolefin article in contact with the aqueous dyebath for a period of at least 20 seconds, and
• (C) removing the polyolefin article so dyed from the aqueous dyebath.