Influence Of Polymer Pretreatments On Digital Textile Printing Of Polyester Fabrics

Digital textile printing technology opens up new world for vivid colours, beautiful patterns and images. Images are possible be printed directly from the computer via printing nozzles onto textiles without the preparation of printing screens. This new technology improves printing process flexibility, efficiency and environmental performance. It provides substantially integrated operations, shortens printing processes and meets the demand for rapid market development. Digital textile printing technology omitted some intermediate stages of the manufacturing processes.Pretreatment for textile is one of the key factors of digital textile printing technology which has great influence on the edge acurity, brilliancy, resolution, and color fixation. The necessary acid or alkaline degree for both dyes and fabrics was not achieved when dispersed dye ink was used for digital textile printing. In addition, the direct printing of digital textile printing inks on PET fabrics bleeds easily because of low viscosity and high surface tension of the ink. So it’s necessary to make surface modification of PET fabrics. Diversity of fabrics leads to diversity of digital textile printing ink. Therefore, ink manufacturers have to develop valid pretreatment. methods for different kinds of digital textile printing ink.In this paper, the pretreatment properties of disperse dye ink based ink jet printing for polyester fabrics was studied in a detail to optimize the pretreatment process.The edge acurity, brilliancy and color fixation was used to assess the digital inkjet printing quality of polyester fabrics which are pretreated by CMC, sodium alginate, PEG and PEO respectively. It was found that the four kinds of polymer pretreatment agents could improve the bleeding degree and image resolution of PET fabrics. PEG and PEO could enhance the color fixation of PET fabrics, while CMC and sodium alginate influenced the color fixation of PET fabrics to a smaller extent. The K/S value of the PET fabrics increased with concentration of CMC, PEG, and sodium alginate. But the K/S value of the PET fabrics pretreated by PEO showed that the K/S value increased first and then decreased a little. PEO was found to be the best pretreatment agent among the four kinds of polymer pretreatment agents for the commercial available digital textile printing ink based on the test results of image quality. When the PET fabrics were pretreated under the optimal conditions with a wide-format digital textile printer, good printing image quality was achieved. The light fastness of was level 7. The friction fastness was level 5, and the washing fastness was level 5.