Study On Composite Modification Of Wool Fabric Surface And Inkjet Printing Properties Of Reactive Dyes

In order to improve the inkjet printing performance of wool fabrics with reactive dyes,the alkaline protease,polymers such as sodium alginate and cellulose derivatives,and cationic surfactants were used to modify the surface of wool fabrics.The spreading and penetration of ink droplets on the fabric were studied,and the influence mechanism of wool scale,polymer membrane structure,etc.on the image quality of reactive dye inkjet printing was analyzed.On this basis,an efficient and environment-friendly surface modification method for wool fabric was proposed.The main research contents are as follows:(1)After protease treatment,the scale on the wool fabric surface was etched,resulting in a decrease of 8% in crystallinity and improved wettability.Therefore,protease treatment not only reduced the diffusion and penetration of ink droplets but also promoted the covalent bonding of reactive dye molecules with reactive groups such as amino and sulfhydryl groups.Compared with the untreated wool fabric,the apparent color depth(K/S values)and fixation rate of cyan,magenta,yellow and black patches increased by 8.2?9.4 and 12.5?23.1 percentage points,respectively,and the permeability decreased by 1.9?17.3 percentage points.Furthermore,it avoided the discharge of wastewater containing absorbable halide(AOX)and excessive damage of wool fabric.(2)When compared with treatment solutions containing sodium alginate(SA)and carboxymethyl cellulose(CMC),carboxymethyl hydroxypropyl cellulose(CMHPC)treatment solution showed the best fluidity,the most obvious elastic behavior and the highest viscosity.Therefore,the thinnest and most continuous films were formed on CMHPC treated wool fabric,which could effectively control the spreading and penetration of ink droplets,thus producing the deepest,brightest and clearest inkjet printing patterns.Compared with SA and CMC treated fabrics,the K/S values of CMHPC treated fabrics were increased by 7.6 ? 8.9 and 3.5 ? 5.7respectively,the fixation rate was increased by 2?12.7 percentage points and 0.5?2.1 percentage points respectively,and the permeability decreased from 6.7% and4.1% to 2.4%,respectively.Moreover,CMHPC treatment reduced the discharge of wastewater containing urea and dyes and the energy consumption of the steaming process.(3)The cationic surfactant octadecyl trimethyl ammonium chloride(STAC)adsorbed on the surface of the protease-treated wool fabric enhanced the electrostatic attraction to the reactive dye anion,blocked some of the pores between the fibers,thereby inhibiting the excessive spreading of ink droplets.Additionally,the improvement of wettability and the phase catalytic transfer and induction effect of STAC promoted the transfer and covalent bonding of dye molecules to the surface of the fabric.Therefore,the inkjet printing performance of wool fabrics was improved.(4)The complex formed by CMHPC and STAC through electrostatic attraction and hydrophobic force were deposited on the surface of the protease-treated wool fabric,forming positively charged films with good wetting properties,which can effectively control the spreading and penetration of ink droplets and promote the combination of dyes and fibers.Therefore,the protease/CMHPC/STAC composite modification further improved the reactive dye inkjet printing performance of wool fabrics,reduced the discharge of urea and dye wastewater,shortened the steaming time,exhibiting broad application prospects.