Preparation Of Disperse Fluorescent Yellow Ink And Its Properties Study

Fluorescent dyes have identical coloring performance with conventional dyestuff, and can also radiate fluorescence. Therefore, dyed fabrics with fluorescent dyes have significant increase in saturation and vividness. Fluorescent dyes have been used in advertising, traffic signs, anti-counterfeit packaging and special places tags because they could give a striking, deep impression. In this paper, disperse fluorescent yellow dye was applied to the heat transfer inkjet printing for polyester fabric. We had studied four sections systematically: preparation of disperse dye paste and its properties analysis, effects of ink components on ink properties, effects of heat transfer conditions on printed fabric performance and printed fabric performance test.Disperse fluorescent yellow paste was prepared with dispersing agent (NNO, MF and CNF) using wet grinding process. The paste centrifugal stability, diffusion, dispersion and thermal properties were tested. The results showed that particle sizes of dye pastes grinded with dispersing agent NNO, MF and CNF after 6 hours were 161.1nm, 150nm and 136nm, the polydispersity indexs (PDI) were 0.327, 0.307 and 0.270, respectively. The dye paste grinded with dispersing agent CNF presented good centrifugal and thermal properties. TEM images demonstrated that the morphologies of dye pastes grinded with dispersing agent MF and CNF were homogeneous nearly spherical nanoparticle and rarely generated agglomeration and precipitation.The ethylene glycol, diethylene glycol, 1,2-propanediol, 1,4-butanediol, glycerol and polyethylene glycol 400 were added to ink formulations. The effects of these polyhydric alcohols on ink viscosity, moisture, shear rheology, thermal stability, color reproducibility, fluorescent reflectivity and fluorescent intensity were studied. The results showed that whenω(polyhydric alcohols) > 15%, ink viscosity increased significantly. Polyethylene glycol 400 and 1,4-butanediol greater impacted on ink viscosity and the moisturizing effect of ethylene glycol was the best. 1,2-propanediol and 1,4-butanediol were not conducive to ink thermal stability properties, significant increase in particle size when heated. All ink formulations presented good color reproducibility, and the color difference (ΔE) of printed fabrics were small. Adding ethylene glycol and diethylene glycol could improve the fluorescence reflectivity and fluorescence intensity of polyester fabric. They could also improve the clarity of printed lines.Surfactant X-100 and NP-12 were used to adjust the ink surface tension. The effects of surfactant on ink surface tension, contact angle, fluorescent reflectivity, fluorescent intensity and printed lines resolution were discussed. The results showed that ink surface tension was reduced significantly when surfactant was added. The permeability properties of ink drops were improved, and contant angle become smaller. However, fluorescent reflectivity, fluorescent intensity and printed lines resolution would be reduced as the ink surface tension was too low.Triethanolamine was used as pH regulator to adjust ink pH value. The effects of pH value on ink conductivity, thermal stability, shear rheology, fluorescence reflectance and fluorescent intensity were studied. The results showed that ink conductivity increased along with the triethanolamine concentration increased. Triethanolamine was conducive to enhance the fluorescence reflectance and fluorescent intensity of printed fabrics. However, the fluorescence reflectance and fluorescent intensity also declined as the content of triethanolamine was over 0.2%.The fluorescent reflectivity and crease recovery properties of printed fabrics were discussed under different heat transfer printing conditions. The printed fabrics presented high fluorescent reflectivity and a slight change in crease recovery properties under the heat transfer condition: 210℃, 30s.In order to compare traditional and inkjet transfer printed fabric performances, apparent shape, color performance, reflectivity, fluorescent intensity, color fastness and bending properties of printed fabrics were analyzed. The results showed that the surface of inkjet transfer printed fabrics was smooth and dye transfer rate was higher. Inkjet transfer printed fabric presented larger brightness, higher reflectivity and fluorescence intensity. Moreover, bending rigidity and bending hysteresis of inkjet transfer printed fabric were relatively smaller, and its soft property was better. In general, the disperse fluorescent yellow ink, which had stable performance and strong fluorescent effect, was suitable for textile inkjet heat transfer printing process. The printed polyester fabric presented a slight change in hand feeling.