Akademik Veri Yönetim Sistemi
Asian Journal Of Chemistry, cilt.4, sa.20, ss.2891-2902, 2008 (SCI-Expanded)
Natural colours have attracted the attention of the entire
world because of their non-hazardous nature. In present study,
woolen fabrics were dyed with natural dyes derived from redonion
(Alliumcepa L.) using various mordants by open bath
dyeing technique. Natural dye (anthocyanins) was extracted
from red-onion skins with acetic acid:ethanol:water (1:80:19,
v/v/v) mixture solution. The amount of total anthocyanins
was determined by using the derivative spectrophotometric
method and found to be 13.5 mg/100 g for fresh onion skin
and 5.2 g/100 g for dry onion skin. Dyeing processes were
carried out according to pre-, together- and last-mordanting
methods by using buffer solutions at the pH = 2-8 interval
and for 1 h at 98-100 ºC. Some metal salts such as Al(OH)3,
Cu(NO3)2, Fe(NO3)2, Zn(NO3)2, NiCl2, SnCl2, Pb(CH3COOH)2
were used as mordantation agents. In addition, various studies
were carried out on the effect of mordant quantity and kind
of mordant salt in dyeing. The colour changes were evaluated
instrumentally with a colour difference meter. Colour differences
in CIE L*a*b* units and gray scale classifications were
reported. Dyeing conditions and other characteristics showed
that mordant was more important than dye in predicting
lightfastness of coloured textiles and good lightfastness which
was between 2 and 4 values were obtained.