Process for the dyeing of polybenzimidazole fibers with anionic dyestuffs
AssigneeCelanese Corporation
InventorsEdward J. Powers, Walter P. Hassinger
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Abstract
Heretofore polybenzimidazole fibrous materials have proven to be extremely difficult to dye successfully. The present invention provides an effective route for the achievement of a satisfactorily dyed polybenzimidazole fibrous material. The fibrous material initially is contacted at an elevated temperature with a liquid (e.g., an aqueous emulsion) comprising an organic swelling agent and salicylic acid to form polybenzimidazonium salicylate, and subsequently is dyed with an anionic dyestuff. Complete and uniform dye penetration is made possible through the use of the present process, and the resulting dyed article is capable of resisting dye sublimation when utilized in an environment where elevated temperatures are encountered.
Claims20
An improved process for the dyeing of a polybenzimidazole fibrous material with an anionic dye comprising:
- a. reacting said polybenzimidazole fibrous material while in a swollen configuration with salicylic acid to form polybenzimidazonium salicylate, and
- b. dyeing said resulting fibrous material with an anionic dyestuff.
An improved process for the dyeing of a polybenzimidazole fibrous material with an anionic dye comprising contacting said polybenzimidazole fibers with a liquid provided at an elevated temperature comprising:
- a. an organic swelling agent for said polybenzimidazole having a solubility parameter when in contact with the fiber of about 11 to 13, and
- b. about 0.05 to 5 percent by weight based upon the total weight of the liquid of salicylic acid,
- whereby said polybenzimidazole undergoes chemical reaction to form polybenzimidazonium salicylate, and dyeing said resulting fibers by contact with a dyebath comprising an anionic dyestuff.
An improved process for the dyeing of a polybenzimidazole fibrous material with an anionic dye comprising contacting a poly2,2'-(m-phenylene)-5,5'-bibenzimidazole fibrous material with an aqueous liquid provided a temperature of about 40.degree. to 97.degree.C. comprising:
- a. about 3 to 20 percent by weight based upon the total weight of the liquid of benzyl alcohol,
- b. about 0.05 to 5 percent by weight based upon the total weight of the liquid of salicylic acid, and
- c. about 0.03 to 0.3 percent by weight based upon the total weight of the liquid of a surfactant,
- whereby said polybenzimidazole undergoes chemical reaction to form polybenzimidazonium salicylate, and dyeing said resulting fibers by contact with a dyebath comprising an anionic dyestuff.
Dependencies are inferred from the claim text.