Comparison of color gamut and fastness properties by using disperse and pigmented-based ink for textile inkjet printing Presented by: Yi Ding Fiber and Polymer Science, College of Textiles North Carolina State University, United States 1 Research background Textile inkjet printing provide new market opportunities for U.S. Key components: Development and improvement of fabric pretreatment agents Evaluation of various colorant sets formulated for Kyocera printheads Optimization of the digital printing process flow Specific studies conducted to date cover: Effects of pretreatment agents on the application of pigment and disperse dye based ink to polyester fabrics for outdoor products requiring lightfastness of 500 hours or more Color gamut analysis as a function of substrates, colorants and pre-treatment chemistries 1
Research Objectives Side by side comparison of pigment/disperse dye-based inksets on polyester color gamut analysis wet and dry crock fastness light fastness Support the dot.com, quick response, and short run manufacturing models for suppliers of multinational retail corporation and others implementing digital printing technologies Experimental Procedure Delphi method is used on decision making, forecasting in technology, education and other fields. relatively strongly structured group communication process, in which matters, on which naturally unsure and incomplete knowledge is available, are judged upon by experts A snowball sampling method effect used to increase the number of expert participants a person selected for study assists the researcher by identifying other relevant people and sometimes, establishing the initial meeting between the researcher and the and the referred person. Questionnaires Choose experts Sending questionnaires No Analyze general ideas Next panel Agreement? Yes Final agreement Analyze feedback Skulmoski, Gregory, Francis Hartman, and Jennifer Krahn. "The Delphi method for graduate research." Journal of Information Technology Education: Research 6.1 (2007): 1 21. Richard Sedlack, Social research: theory and methods, 1992 4 2
Experts Identification 40 Experts were contacted, 13 of them replied with willingness to participate, including: Color scientist, Printer manufacturer, Textile printing industry specialists Ink manufacturer, Color management experts >2/day 1/day 1/week 1/two weeks 1/month 1 3 years 3 5 years 5 10 years 10~20 years >20 years Experts working frequency Experts working experience 5 Process Model for Color Gamut Analysis Fabric and printer preparation Characterization and profile creation Profile creation Profile input Color gamut analysis 2D and 3D gamut visualization Gamut volume White point colorimetric value Maximum black Delta E value under different rendering intent Print quality evaluation Light fastness Dry/wet crock fastness Wash fastness Color matching evaluation Ink consumption Customization evaluation 3
Technology MS JP5Evo (Kyocera print heads) RIPMaster v11 X-rite i1profiler version 1.6.3 Color Think Pro v3.0.3 Origin 6.0 7 Experiment methods Ink comparison between: Inkset A (Disperse-based) 1 st generation: CMYK 2 nd generation: CMYK+Red, Blue, Purple Inkset B (Pigment-based) 1 st generation: CMYK+Red,Blue 2 nd generation: CMYK+Red, Blue, Orange, Green CTB and ICC profile Lightfastness and crock fastness AATCC standard 8 4
Individual color comparison L* 100 80 60 40 20 0 Cyan Magenta Yellow Black Blue Red C* 80 60 40 20 0 Cyan Magenta Yellow Blue Red Inkset A Untreated Inkset A Pretreated Inkset B Untreated Inkset B Pretreated 9 Gamut Comparison Inkset A 4c & 7c 10 5
12/14/2016 ICC Color Gamut Comparison Inkset A1 Inkset A2 Inkset B1 Inkset B2 Inkset Gamut volume A1 (4c) A2 (7c) B1 (6c) B2 (8c) 135,687 186,533 152,317 188,426 Gamut Comparison between Inkset A and B (4 colors) Pigment Inkset B 4c Disperse Inkset A 4c Inkset Inkset A 4c Gamut volume 135,687 Inkset B 4c 161,305 12 6
Gamut Comparison between Inkset A and B (7 colors) Pigment Inkset B 7c Disperse Inkset A 7c Inkset Gamut volume Inkset A 7c 186,533 Inkset B 7c 168,825 13 Crock fastness D/W D W Color Inkset A Inkset B Weft Warp Weft Warp Cyan 5 5 1.5 2 Magenta 5 5 2 2 Yellow 5 5 2 2 Black 4.5 5 2 2 Red 4.5 5 2 2 Blue 5 5 2 2 Orange 5 5 2 2 Green 2.5 3 Cyan 5 5 1.5 1.5 Magenta 5 5 2.5 2.5 Yellow 5 5 2 1.5 Black 4.5 5 2 2 Red 4.5 4.5 2 2.5 Blue 5 5 2 2.5 Orange 4.5 5 2 2 Green 3 3 14 7
Light fastness Color Cyan Magenta Yellow Black Red Blue Violet Green Exposure levels (h) Inkset A Inkset B 160 2.5 4.5 300 2.5 4 500 2 3.5 160 3.5 5 300 3 4.5 500 2 4 160 3.5 4.5 300 3 4.5 500 2 3.5 160 3.5 4.5 300 2.5 4.5 500 2 4 160 3.5 3.5 300 2.5 3 500 2 3 160 3 4 300 2 4 500 1.5 3.5 160 2.5 4 300 1.5 3.5 500 1 3 160 3.5 300 2 500 1 Conclusion Pretreatment enhances fiber receptiveness for the inks, leading to increased color intensity and color gamut. The particulate nature of pigments can lead to superior light fastness over disperse dye-based inks; the disperse dye based inksets did not give satisfactory light fastness at 300-500 h exposure levels. The inability of pigment particles to diffuse into the fibers during the fixation step can lead to crock fastness problems. Disperse dye inksets provided deeper color shades on PET, the L* of black color was much lower in Inkset A than in Inkset B, which would be helpful in increasing the color intensity for the prints. 8
Current Limitations and Possible Solutions Selection of ICC profiles, lead to a bigger color mismatch between original design and final reproduced product; 17 Current Limitations and Possible Solutions Metamerism issue causing by different illuminant source and ink recipe difference. Some CMS software are trying to solve those problems by skipping creating ICC profile for the color reproduction, by using innovation ideas of ink recipe for color matching. Reflectance RGB CIEXYZ CIELAB CMYK Reflectance CMYK Daylight Fluorescent 18 9
Current Limitations and Possible Solutions Shrinkage correction Spectrophotometer development for textile substrate Lack of standard The lack of standard for color gamut volume measurement unit; the lack of standard for the textile substrate to specify the performance of ink and printer Lots of variables need to be controlled during this process The reproduction requirements for the customer are different due to different uses or purposes Compromises need to achieve the best print quality for a large scale production, instead of for one perfect sample run Maintain a balance between production costs and the print quality 19 Acknowledgements Walmart US manufacture Innovation Fund Instruction from Professors. Freeman, Chapman, Shamey Color experts participate the interview or provide contacts Technical support staff in College of Textiles and Department of Chemistry of North Carolina State University 20 10
21 11