Despite the increasing use of digital printing technologies, screen printing remains crucial in applications that use special printing inks. It adds value to a product with increased decoration or functionality. The diploma thesis involves the analysis of puff ink printed on 100 % cotton fabric. For printing we used two different sizes of screen, one with a lower weave density (4380, 0°, 15 N) and the other with a higher weave density (6164, 0°, 15 N). The adhesion of the printing ink to the fabric is very good and after analysis, we found that it belongs to the ISO Class: 1/ASTM Class 4B classification. Rubbing resistance was tested for dry and wet rubbing. The samples were analysed with ImageJ, which measured the mean grayscale value of the clean non-printed fabric, the printed fabric, and against the imprint. From the differences in the mean grayscale values, we found that wet samples were less resistant to rubbing than dry samples. Printed raster dots were analysed with ImageJ and the results were dot gain, but the differences between printed raster dots and original raster dots were minimal and unnoticeable to the eye. Resistance to washing was tested at several different temperatures. Washing was done at 40, 60 and 95 °C. Spectrophotometric measurements were performed to evaluate the influence of the washing process at different temperatures on the imprint. For washed samples at 40 and 60 °C, the colour difference was minimal, while the colour difference was still moderate on the samples washed at 95 °C. Colour fastness in hot ironing was tested with the wet ironing test. Visual assessments on a grayscale showed no transient ink on the white fabric. Also, there was no change in the colour of the samples after ironing. Therefore we have realised that the puff ink MINERFOAM SR, manufactured by MINERVA S.p.A, Italy, mixed with the black pigment NERO, manufactured by MINERVA S.p.A, Italy, enables the production of high quality prints on 100 % cotton fabric.
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