Preparation And Jetting Properties Of Black Reactive Dye Inkjet Printing Ink

Reactive dye inks are widely used in ink-jet printing of cellulose fibers such as cotton,hemp and protein fibers such as silk due to their wide color gamut,high fastness and bright color.Black reactive dye ink is an essential variety of ink.Due to the requirements of deep color and high blackness,it is difficult to prepare high-quality black reactive dye ink.In this study,reactive black 8 dye was selected to prepare high concentration black reactive dye solution with single dye,and two high concentration black reactive dye solutions with different dye ratios were prepared.In this study,three kinds of high concentration black reactive dye solutions were prepared by dye compounding,and the effects of ethylene glycol,diethylene glycol and 1,2-propanediol on the dye cluster structure,jet performance and printing quality of three kinds of black reactive dye solutions were studied.The influence of polyol type and dosage on dye clustering was analyzed by UV Vis absorption spectroscopy and conductivity method;The effects of solvents on the viscosity,surface tension and moisture retention of black reactive dye solution were studied;The effect of polyols on the morphology of black reactive dye solution was investigated by using a high-speed ink-jet observation system;Finally,through the ink-jet printing on cotton fabric,the influence of solvent on the image clarity and color performance of ink-jet printing fabric was explored.The results show that ethylene glycol,diethylene glycol or 1,2-propanediol can reduce the aggregation of dyes,and the effect of diethylene glycol is the most obvious.The addition of the above three solvents can increase the viscosity and decrease the surface tension of the dye solution,but the effect is different.Among them,diethylene glycol has the most obvious effect on the increase of viscosity,and 1,2-propanediol has the strongest ability to reduce the surface tension.The addition of polyols can effectively avoid the formation of satellite ink droplets and improve the clarity of pattern contour.In addition,it was found that with the increase of polyol concentration,the permeability of ink to fabric could be significantly improved,and the color fastness was not affected.