The purpose of this thesis is to explain how it is possible to replace the synthetic dyes with the natural ones in the textile industry, to use them as before in terms of smaller global and ecological production.
An experiment was made by dyeing raw cotton and raw wool with a natural red dye called Carmine, obtained from dried female cochineal insects (Dactylopius coccus), native to South America. Three different mordants were used, which in different pH media caused a different range of color shades, from yellow to deep red and purple.
After the experiment, the colored samples were spectrophotometrically evaluated using the CIE L* a* b* color space.
The results show that the wool samples absorbed more cochineal dye than the cotton samples. The deepest color strength was achieved when wool and cotton samples were dyed in an acid dye bath, however in the alkaline dye bath the samples did not absorb the dye, they only turned slightly yellow. As for the mordants used, cotton and wool samples had the highest K/S value when mordanted with aluminum sulfate. The lowest color strength was obtained by the samples that were not mordanted.
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