Improve The Application Performance Of C.I. Reactive Blue 19

Owning to pure colored light and excellent fastness, C.I. Reactive Blue 19 plays an important role in the reactive dyestuffs. The reactive group of C.I. Reactive Blue 19 isβ-hydroxylethyl sulfone sulfate, which converts to vinyl sulfone structure in alkali liquor and has high substantivity for cotton and regenerated cellulose fibers with high dye-uptake.Only one strong hydrophilic group (-SO4Na) remains because the sulfuric acid ester group is apt to be taken off in strong alkali liquor. As a result of the weaker electrostatic repulse between the molecules, aggregates is easy to be formed, uneven dyeing is more serious especially when the dyeing concentration is high or the dyeing ratio is low with the existence of salt and alkali.Some measures have been proposed by dyers for this problem. For example, though it has been improved in some extent by raising temperature slowly or feeding in alkali in batches, it is difficult to master the technology because of so many processes and stronger labour strength. Besides, in the process of producing dyestuff,β-naphthalene sulfonate(N)-formaldehyde(F) condensates is used to be added. However, it is hard to be degraded and it causes environmental pollution because of the existence of free formaldehyde.In order to solve the problem in a more environmental way, firstly we optimized synthetic process at lower ratio of F to N and got N-F condensates with excellent dispersive ability. Secondly, some anionic or nonionic surfactants which were biodegradable and had outstanding disperse ability were selected, then mixed them with N-F condensates. Lastly, the influence of auxiliaries and alkali on dye absorptivity, fixation, colored light and buildup were investigated in exhaust dyeing, and the dyeing process had been optimized.The results showed that the product named R110107 was excellent which was synthesized on the condition that reaction starting acidity was 22%, the ratio of N/F was 1:0.3, heat preservation time was 1.5h, heat preservation temperature was 110℃. Then other anionic and nonionic surfactants were selected, we found that polyvinylpyrrolidone K-30 and caprolactam were suitable for cold pad-batch dyeing while sodium lignin sulfonate and anthraquinone-2-sodium sulfonate were appropriate for exhaust dyeing. The usage of R110107 could be reduced by these additives. In exhaust dyeing, after investigating the influence of auxiliaries and alkali on dye absorptivity, fixation, colored light and buildup, we found that R110107 was excellent in comparison with crude dyestuff dyeing, a little influence was caused by adding anthraquinone-2-sodium sulfonate, serious influence happened by adding sodium lignin sulfonate. Almost 10% of dye absorptivity and fixation were reduced, buildup was reduced severely, brightness was almost reduced from 43.7 to 42.94. C.I. Reactive Blue 19 was more stable when the alkali was QF-4 although the degree of fixation decreased a little. The degree of fixation could be kept and better level dyeing could be obtained by adopting the craft of feeding in a little sodium carbonate in advance. Almost two thirds cost of alkali would be decreased by adopting this craft, so the application prospect is wonderful.