Multivariate Model for Characterising Physical Dot Gain, Chroma and Lightness in Offset Lithography

Document Type : Original Article

Authors

Department of Printing Technology, School of Engineering, Avinashilingam Institute for Home Science and Higher Education for Women, P.O. Box: 641108,Coimbatore, Tamil Nadu, India

Abstract

Bright print images help any product on the shelf stand out, attract the consumer, and add a unique value to the product. This research work is to empirically identify significant factors and optimize printing press parameters like press speed (x1: 5000, 7000, and 9000 sheets per hour), ink viscosity (x2: 15, 25, 35 Pa·s), and blanket rubber hardness (x3: 65, 70 and 75 shore A) to achieve prints with rich chroma yet with low dot gain in the lithography process, the most economical and widely used process today in the field of label and packaging industry. The parameters used during the printing process can affect the physical dot gain and the color of printed images. To study this, measurements were taken of the dot gain (y1) and color (measured in terms of lightness (y2) and chroma (y3)) at three different dot areas - highlight (25 %), middle tone (50 %), and shadow (75 %). Box-Behnken Design was used to test fifteen different print conditions. The second-order polynomial model's fit quality was good concerning the responses. The optimum printing machine conditions determined to minimize dot gain and lightness and maximize chroma were a press speed of 5000 sheets per hour, 30 Pa·s ink viscosity, and blanket rubber having 70 A shore hardness. The optimized values agreed with the predicted responses were acceptable, considering the right balance of minimum dot gain, higher chroma, and lower lightness to give the vibrant yet controlled halftone dot area in print production.

Keywords

Main Subjects

References

  1. Igor Z, Stanislav B, Zdenka B. The Colour characteristics of modern printing. Conference on Colour in Graphics, Imaging, and Vision; January 2002; Springfield: Society of Imaging Science and Technology; p. 545-548. https://doi.org/10.2352/ cgiv. 2002.1.1.art00114.
  2. Namedanian M. Characterization of halftone prints based on microscale image analysis [PhD dissertation]. [Linkoöping]: Linköping University Electronic Press; 2013. https://doi.org/10.3384/diss. Diva -99791.
  3. Namedanian M, Nyström D, Zitinski Elias P, Gooran S. Physical and optical dot gain: characterization and relation to dot shape and paper properties. In: Color Imaging XIX: Displaying, Processing, hardcopy, and Applications. 3 February 2014; California. SPIE. P.69-78. https://doi.org/10.1117/12.2035713.
  4. Ferreira SLC, Bruns RE, Ferreira HS, Matos GD, Davit JM, Brandão GC, et al. Box-Behnken design: An alternative for the optimization of analytical methods. Anal Chim Acta. 2007: 597(2): 179-186. https://doi.org/10.1016/j.aca.2007.07.011.
  5. Saleh AG. The analysis of the dot gain problems and its effect on colour reproduction. InTAGA Proceedings. 1982.
  6. Malmqvist K, Verikas A, Bergman L. Consistency of Mechanical Dot gain-A hidden Quality Parameter. InTAGA 1999; (409-417).
  7. Xue Jia X, Qing Huang B, Fu Wei X. Study on the influence of rheological properties on the printing quality of ink. Advanced Materials Research; July 2011. Crossref: Trans Tech Publications, Ltd; p. 2018-2021. https://doi.org/10.4028/www.scientific.net/ AMR. 284-286.2018.
  8. Jurkiewicz A, Pawlikowski M, Pyryev Y. Analytical, numerical and experimental analysis of pressure force between two rollers axes distance and the contact zone. Intern J Mechan Sci. 2017; 131(132): 722-727.https://doi.org/10.1016/j.ijmecsci.2017.07.030
  9. Shen-yu Chang. A Dot-gain Analysis of Inkjet Printing. 2001; 364-368
  10. Tutak D, Beytut HN, Ozcan A. Investigation of the effects of different ink density value on color gamut in offset printing. J Graph Eng Design. 2018; 9(1): 23-28. https://doi.org/10.24867/JGED-2018-1-023.
  11. John J. McCann. The appearance of brightness and lightness. on: color and imaging conference. January 2000. Springfield: Society of Imaging Science and Technology; p.18-23. https://doi.org/10.2352/cic. 2000.8.1.art00005.
  12. Albert H. Munsell. A Color Notation: A Measured Color System Based on the Three Qualities, Hue, Value and Chroma with Illustrative Models, Charts and a course of Study Arranged for Teachers. 2nd ed. Boston: Geo. H. Ellis Co. 1907.
  13. Quentin Shaw M, Sharma G, Bala R, Dalal E. Color printer characterization adjustment for different substrates. Color Research and Application: Endorsed by Inter-Society Color Council. The Color Group (Great Britain), Canadian Society for Color, Color Science Association of Japan, Dutch Society for the Study of Color, The Swedish Colour Centre Foundation, Colour Society of Australia, Centre Francais de la Couleur. December 2003; 28(6): 454-467. https://doi.org/10.1002/col.10198.
  14. Zhuravleva GN, Syltanova YM, ARovenskikh A, Yamilinets YS. The effect of washes on the offset rubber blanket. In: IOP Conference Series: Earth and Environmental Science; August 2020; 548. IOP Publishing Ltd; https://doi.org/10.1088/1755-1315/ 548/6/062051.
  15. Sharma A, Starr B. Evaluation of ink optimization technology in offset color printing. J Imag Sci Technol. 2010; 54(6): 0605041-060504-13. https:// doi.org/10.2352/J.ImagingSci.Technol.2010.54.6.060504.
  16. roman16 bvdm Reference Images (EN) [Internet]. Deutschland: Bundesverband [cited 2023 Dec 21]. Available from: https://www.bvdm-online.de/ 
    bvdm/ branchenportal/technik-innovation/normen-und-standards/standardwerke/roman16-bvdm- reference-images-en.
  17. Hsich YC. Measuring Dot Gain from Film to Plate: Murray Davies or Yule-Nielsen Equation. Vis. Commun. J. 1998; 24-30.
  18. Douglas C. Montgomery. Design and analysis of experiments. 10th ed. John Wiley & Sons; 2017.
  19. Fernandez M, Munoz ME, Santamaria A, Azaldegui R, Diez R, Pelacz M. Rheological analysis of highly pigmented inks: Flocculation at high temperatures. J Rheology; 1998; 42: 239-253. https://doi.org/10.1122 /1.550948.
Progress in Color, Colorants and Coatings
Volume 17, Issue 4 - Serial Number 55
October 2024
Pages 365-380

Files

Share

How to cite

Statistics