Effect Of Surface Modification Based On Cellulose Ether And Chitosan On The Properties Of Silk Inkjet Printing

Silk fiber belonged to protein fiber,and its fabric had many excellent wearing properties,such as skin breathability,soft feeling,elegant appearance,high glossiness,and was often used to produce high-quality clothing and household products.In the field of textile printing,inkjet printing has greatly expanded the space of clothing design,improved the grade of products,and met the needs of consumers for colorful and personalized printing products.Inkjet printing made silk fabrics more aesthetic and practical.The application of digital inkjet printing to produce customized silk printed fabrics has been a research hotspot in related fields.However,due to the porous structure and poor water retention of the silk properties,the printed fabric has problems such as poor color performance,serious infiltration and low fixation rate,which was difficult to meet the needs of actual production and processing.Therefore,before inkjet printing,it was necessary to modify the silk properties to improve its inkjet printing quality.Based on this,two pretreatment methods were selected to modify the surface of silk fibers.The surface structure and properties of the modified fabrics were characterized by scanning electron microscope(SEM)and contact angle measuring instrument.The mechanism of the spread of micro-upgrading and picoliter ink droplets on the fiber and the improvement of printing effect were explored.The inkjet printing effect of different pretreatment methods was evaluated.At the same time,on the basis of improving the inkjet printing performance,it provided antibacterial performance,increased the added value of silk printed fabrics,and widens the market application of silk printed fabrics.The specific contents and research results were as follows:(1)In this paper,sodium alginate(SA),hydroxyethyl cellulose(HEC)and hydroxyethyl methyl cellulose(HEMC)were used to pretreat the surface of silk fabrics.Scanning electron microscopy(SEM),contact angle and other studies showed that polymer pretreatment could form a membrane structure on the surface of silk fabric,build a new surface,and inhibit the infiltration of ink droplets on the fiber by blocking the fiber gap and improving the surface hydrophobicity.Compared with SA and HEC,HEMC showed the best rheological properties and surface activity.The content of C-O-C and hydrophobic group C-C/C-H on the fabric treated by HEMC was the highest.A relatively hydrophobic new surface was constructed on the surface of silk fabric,with a hydrophobic angle of97.7°,which can effectively control the spreading behavior of ink droplets.(2)The spreading behavior and deposition of leather upgraded ink droplets and micro upgraded ink drops on the surface of different pretreated silk fabrics were investigated.The hydrophobic segment chain of HEMC film faces the air side,which makes the interaction between film and ink limit the spreading movement of ink droplets on the fabric surface,thus significantly improving the inkjet printing performance of silk fabrics.The apparent color yield,line fineness and penetration of the printed color blocks of HEMC pretreated fabrics are the best,followed by HEC,and SA was the worst.Among them,the K/S of the three colors was 6.8,10.4 and 9.1 higher than that of the non-polymer treated fabrics.The length and width of the line have been reduced by 315μm and 25μm,respectively.The spreading area was reduced by about 100～175 mm~2.The results showed that the polymer pretreatment regulated the spreading behavior and deposition of ink droplets on the fabric surface by constructing a new surface,improved the quality of inkjet printing patterns,and increased the utilization rate of different color dye inks by 68.7～80.0%,which is expected to be applied to large-scale industrial production.(3)Dialdehyde chitosan was obtained by selective oxidation of chitosan with sodium periodate.When the mass ratio of chitosan to sodium periodate was 1:1.2,the aldehyde content of oxidized chitosan reached the maximum.The Scanning Electron Microscope showed that dialdehyde chitosan and chitosan were successfully crosslinked on the fibers.The printing performance showed that under the weak acid condition,the amino group in the chitosan molecule made it positively charged,and formed electrostatic interaction with the negatively charged reactive dye molecule,thus increasing the reactive dye reaction sites,increasing the adhesion of the reactive dye,and significantly improving the color strength and impermeability of the fabric.Moreover,DACS crosslinked chitosan pretreated fabric showed strong antibacterial activity against Escherichia coli and Staphylococcus aureus.The antibacterial property increased the added value of silk printed fabrics and widen its application in antibacterial textiles.