Microstructure Control And Application In Inkjet Printing Of Polymer/organic Pigment Composite Latex

Digital inkjet printing technology is known as the most market-valued printing and dyeing process in textile industry in the 21 st century due to its individual requirements,green environmental protection and convenient production characteristics.As an important component and main consumable of inkjet printing technology,ink can account for about 40% of the total production cost.It can be seen that the research and development of ink must be paid attention to in the process of realizing the industrialization of digital inkjet printing.Organic pigment-based digital inkjet printing inks have attracted much attention in the research and development of digital inkjet printing due to their bright colors and complete varieties.However,the development of organic pigments has been hindered by problems such as low surface polarity,poor dispersion stability and poor weather resistance.Research shows that the introduction of the dispersant can form an adsorption layer on the surface of organic pigments,thereby improving the wettability of the organic pigment surface and improving its dispersion stability state.Nevertheless,in the external environment,such as alternating cold and heat,the outer dispersant of the organic pigment is prone to occur desorption,resulting in the pigment particles re-agglomeration and the deterioration of dispersion stability,which is undoubtedly not conducive to the use of the pigment.Based on this,effective measures are taken to carry out the dispersion and stabilization treatment on organic pigments,and then change the surface polarity of organic pigments,improve hydrophilicity,and further enhance their dispersion stability in the aqueous medium.By modifying the surface of the dispersed organic pigment particles and introducing polymer molecular chains to provide steric hindrance stability,the relationship between the dispersant on the surface of organic pigment and the polymer was established,and the adsorption of the dispersant on the outer layer of organic pigment particles was enhanced.The polymer/organic pigment composite latex was prepared for the red,yellow and blue organic pigment inkjet printing ink,and its printing performance was studied.The detailed works are as follows:Firstly,the anionic surfactant with amphiphilic group and active site of vinyl reaction was used as the dispersant.Since the copper atom in the organic pigment particles can adsorb the anionic dispersant,the dispersant could form a boundary adsorption layer on the surface of the organic pigment.The organic pigment particles are refined by ball milling process,and the optimal dispersion process is determined by investigating the ball milling dispersion process parameters.The prepared organic pigment dispersion has good dispersion stability and basic properties such as particle size,viscosity,surface tension and surface tension,all met the ink needs.In addition,in order to change the surface dispersant adsorption layer of the organic pigment dispersion liquid to withstand the influence of environmental factors,the above-mentioned dispersant is still applied as an emulsifier,while styrene(St)and butyl acrylate(BA)are added for monomer copolymerization.The polymer can be covalently bonded with the active sites of the dispersant on the surface of the organic pigment,thereby preventing the migration of the dispersant and helping to stabilize the adsorption of the dispersant on the surface of the organic pigment particles.Even after the subsequent printing and film formation,the surfactant is still attached to the organic pigment particles and will not be decomposed,thus improving the use value of the organic pigment and saving the actual cost.Finally,by adding relevant additives to the as-prepared polymer/organic pigment composite latex,the red,yellow and blue three primary colors of organic pigment inkjet printing ink are prepared.The self-made ink was sprayed on the surface of the fabric by using the self-controlled three-dimensional liquid distribution system to simulate digital inkjet printing.The wearing properties of the printed fabric after printing were studied,and the actual application effect of self-made polymer/organic pigment composite latex inkjet printing ink was investigated.The printing fabric with bright color and clear pattern was obtained.Besides,the ink could also be used for writing on A4 paper,and the writing effect with smooth writing and bright line segment was obtained.The above results show that the self-made organic pigment inkjet printing ink has practical application value.