Preparation and properties of disperse dye nanocapsule inkjet printing ink
Objective In order to improve the stability and inkjet fluency of disperse dye inkjet ink,core-shell disperse dye nanocapsules(DDNC)were prepared,and the influences of glass transition temperature and thickness of disperse dye nanocapsules shell on the stability,filtration and ink-jet printing performance of the ink were studied.Method The DDNC were prepared via emulsion polymerization by using copolymer(P(MMA-co-BA))of methyl methacrylate and butyl acrylate as shell and C.I.Disperse Purple 93 as core.Then the DDNC were configured as ink-jet printing ink,and thermal stability,storage stability,centrifugal stability and filtration performance of the DDNC ink were tested.DDNC ink was used for polyester fabrics.Scanning electron microscope(SEM),spectrophotometric color meter,fabric style testing instrument and fastness meter were adopted to characterize the morphology,color performance,hand feeling and color fastness of the printed fabric.Results The results show that core-shell DDNC were successfully prepared and the glass transition temperature and thickness of P(MMA-co-BA)shell could be controlled by adjusting the proportion and amount of comonomers.the DDNC ink demonstrated significant improvement in thermal stability,storage stability and centrifugal stability compared with C.I.Disperse Purple 93 ink,which is attributed to the shield of the P(MMA-co-BA)shell.The stability of the DDNC ink could be improved by increasing the glass transition temperature of the shell and adopting reasonable shell thickness.When the glass transition temperature of the P(MMA-co-BA)shell was 67.6℃and the thickness of the shell was 87.5 nm,the thermal stability,storage stability and centrifugal stability of DDNC ink reached 81.6%,96.6%and 80.5%,respectively.The P(MMA-co-BA)shell with high glass transition temperature avoided film forming during the filtration process,thus reducing plugging of PVDF filter membrane pores.However,the particle size of the DDNC demonstrated a remarkably increase when the P(MMA-co-BA)shell became sufficiently thick,resulting in the reduction of filtration flow rate.DDNC ink showed a better filtration performance with a high flow rate of 5 mL/s to penetrate through PVDF filter membrane when the glass transition temperature of the P(MMA-co-BA)shell was 67.6℃and shell thickness was 87.5 nm.Optical images of the DDNC ink inkjet printing polyester fabrics displayed a bright color and clear pattern while C.I.Disperse Purple 93 ink failed to penetate properly,indicating that DDNC ink has good ink-jet performance and the P(MMA-co-BA)shell on the surface of the disperse dye could effectively improve the ink-jet performance without affecting color brightness.SEM shows a thin film formed on the surface of the printed polyester fabrics due to the P(MMA-co-BA)shell of the DDNC,which is conducive to improving the color fastness of the printed fabric.The rubbing and washing fastness of the printed fabrics reached grade 5.Conclusion The glass transition temperature and thickness of P(MMA-co-BA)shell can be controlled by adjusting the proportion and amount of comonomers,and the stability of the ink can be improved by increasing the glass transition temperature of the shell and adopting reasonable sbell thickness.When the glass transition temperature of P(MMA-co-BA)shell is 67.6℃and the thickness of the shell is 87.5 nm,the thermal stability,storage stability and centrifugal stability of DDNC ink can reach 81.6%,96.6%and 80.5%,respectively.The DDNC ink shows a better filtration performance with a high flow rate of 5 mL/s to penetrate through PVDF filter membrane.The fastness of printed fabrics can reach grade 5 with a soft hand feeling.This study offers an effective approach to improve the ink-jet performance of disperse dyes,with good application prospects in inkjet printing.