The objective of this diploma thesis was to observe the influence of adding conventional pigment (KP), phosphorescent pigment (FS) and microencapsulated thermochromic dye (TK) on the photocolouration of cotton fabric printed with microencapsulated photochromic dye (FC). Seven printing pastes of different compositions were prepared. The printing pastes were applied to a 100% cotton fabric by a flat screen printing process. The printed samples undergone measurements of mechanical and physical properties, colour and colour fastness to washing and light. The colour of the samples was spectrophotometrically evaluated. Values of thickness, mass per surface area, stiffness, breaking strength and elongation increased on all printed samples, whilst values of air permeability decreased by one third compared to unprinted fabric. The addition of KP, FS or TK into the printing paste, which already contained FC, reduced the photocolouration of the fabric. Moreover, KP had the lowest and TK the highest influence on the fabric photocolouration. With the increase of rubbing cycles, the photocolouration of the printed samples worsened. The biggest influence was observed with the addition of KP and the lowest with the addition of TK. With the increase of laundering cycles the colour fastness of the printed fabric decreased. The addition of any kind of colourant into the printing paste which already containing FC worsened the colour fastness to washing of the fabric printed with microencapsulated photochromic dye. Prolonging the time of illumination of the samples in the Xenotest apparatus decreases the colour fastness of the samples to light. The addition of KP, FS or TK into the printing paste, which already contains FC, slightly improves the colour fastness to light of the cotton fabric printed with FC.
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