Study On Inkjet Printing Effect Of Reactive Dyes On Cationically Modified Cotton Fabrics

Ink jet printing of cotton fabric has excellent wearing comfort performance and is deeply loved by consumers.The cationic cotton fabric is easy to be stained white in the washing process.After cationization,it can be treated with sodium alginate to improve staining white,but the reactive dye could not contact with the fiber directly,which affects the dye utilization.The cotton treated with sodium alginate will consume a lot of water resources in the process of washing,and the treatment method contains a lot of urea,which increases the pressure of ecological environment.In order to obtain highquality ink-jet printing products of cotton fabric,improve the utilization rate of dyes,avoid white staining,and emission reduction,ecological environment protection,this study carried out full cationic modification of cotton fabric using cationic modifier(2,3-epoxypropyltrimethylammonium chloride)and direct ink-jet printing using reactive dye inks without pretreatment of sodium alginate,through electrostatic force to let reactive dyes and fabrics to combine to limit dye movement.The effects of the composition and content of the modified solution,steaming time and additives on the ink jet printing were studied.The surface structure and properties of the fabric were characterized by SEM,XPS,IR and contact angle.The results show that the larger the mass fraction of the modifier(2,3-epoxypropyltrimethylammonium chloride),the better the staining,the darker the apparent color of the four colors(C,M,Y,K),the smaller the spreading area;when the mass fraction of sodium hydroxide is 1%-2%,the staining is best,the apparent color of the four colors is the largest and the spreading area of the ink drops is the smallest;increasing the steaming time can improve the staining on white ground,but the spreading area of the ink drops also increases.In the ink-jet printing of cationic cotton fabric with reactive inks,increasing the amount of modifier and proper sodium hydroxide content can make cotton fabric obtain stronger electrostatic force,improve the white ground staining,reduce the discharge of colored wastewater,and improve the color effect and clarity of ink-jet printing.When the mass fraction of the modifier reaches 12%,the K/S value of the four color blocks is the largest,the K/S value of the white ground and the absorbance of the washing residue are the smallest,the white ground staining is the best,and the linewidth is the closest to the actual value;when the mass fraction of sodium hydroxide is 1%-2%,the K/S value of the four color blocks is the largest,the K/S value of the white ground and the washing residue are the smallest,the white ground staining is the best,and the linewidth is the closest to the actual value.Using sodium carbonate can not get a good ink-jet printing effect;when the cold stacking time is more than 24 hours,the effect on the inkjet printing effect is not obvious.In the ink-jet printing of cationic cotton fabric with reactive inks,increasing the steaming time properly and using a small amount of auxiliaries can promote the combination of the reactive dyes and the modifier by ion bond,and realize the four color have no staining of white ground at the same time.When the steaming time reaches 20 min,the K/S value of the three color blocks except cyan is the largest,the white ground has no staining,the line width change is less than0.05 mm,the steaming time can improve white ground staining of cyan;when the urea dosage is 5% or the glycerin dosage is 7%,the white ground has no staining,the K/S value of the white ground is the same as the blank sample,the K/S value of the color block is the best,the permeability is less than 10%,and the line width change is less than 0.05 mm.The optimal ratio of alkali to modifier in the cationic solution is 1:8.When the content of alkali and modifier is 1.5% sodium hydroxide and 12% modifier;when the dosage of additive is 5% urea or 7% glycerin,the fabric has good fastness,little change of tensile strength in warp and weft direction,bright color and clear outline of ink-jet printing pattern.The results show that compared with baking,steaming and impregnation,the utilization rate of modifier by coid batch is the highest.Compared with the unmodified cotton fabric,the cationic modified cotton fabric has the following advantages: the yarn becomes thicker,and the surface roughness of the fiber decreases;the contact angle is115°,the surface hydrophobicity of the fabric increases;the nitrogen element increases obviously,and the peak value of XPS and IR spectrum changes obviously.The utilization rate of the modifier was not significantly improved by increasing the cold reactor time;when the salt content in the modified solution was 1g/L,the utilization rate was increased by about 6% compared with that without salt;when the amount of sodium hydroxide was 1.5% and the amount of sodium carbonate was 3%,the utilization rate of the modifier was increased by about 3%.This study has practical application value to improve the effect of cationic cotton in ink-jet printing,and provides a technical way to solve the problem of white ground staining and reduce the discharge of colored wastewater.