The Influence of Mordanting with Silver Nitrate on the Dyeability and UV Protection of Cotton Dyed with Green Tea
Vpliv čimžanja s srebrovim nitratom na obarvljivost in UV-zaščito bombaža, pobarvanega z zelenim čajem

Marija Gorjanc, Rosana Sluga Štih, Iris Vrhovski, Monika Curk
2015 Tekstilec  
Silver nitrate (AgNO 3 ) was used as a mordant for dyeing cotton fabric with natural dyes. Due to the high concentrations of catechin and tannin, green tea was used as a natural dye. The green tea extraction was performed under neutral and alkaline conditions. Four molar concentrations of AgNO 3 were used, namely 1, 5, 10 and 50 mM. Mordanting was performed during dyeing with green tea extracts. The colour (CIE L*a*b* values) and UV protection factor (UPF) of the dyed cotton samples before and
more » ... samples before and after ten repetitive washings were measured spectrophotometrically. The results revealed that with the increase of the molar concentration of AgNO 3 , the samples became darker, redder and bluer. Dyeing with alkaline green tea extract was not as successful as dyeing with neutral green tea extract. Diff erent shades of cotton were achieved when dyeing with neutral green tea extract and mordanting with diff erent molar concentrations of AgNO 3 . Using 50 mM AgNO 3 achieved a very dark grey (almost black) colour. Cotton samples dyed with neutral green tea extract had excellent UV protective properties (50+), some even after washing. Izvleček Pri barvanju bombažne tkanine z naravnim barvilom je bil kot čimža uporabljen srebrov nitrat (AgNO 3 ). Kot naravno barvilo je bil uporabljen zeleni čaj, saj ima visoko vsebnost katehina in čreslovine. Barvilo zelenega čaja je bilo ekstrahirano pri nevtralnih in alkalnih pogojih. Čimžanje je bilo opravljeno med barvalnim postopkom, z uporabo štirih molarnih koncentracij AgNO 3 , in sicer 1, 5, 10 ter 50 mM. Barvo (CIE L*a*b* vrednosti) in UV-zaščitni faktor (UZF) pobarvanih bombažnih vzorcev smo spektofotometrično izmerili pred 10 zaporednimi pranji in po njih. Rezultati kažejo, da z večanjem molarne koncentracije srebrovega nitrata postanejo barve vzorcev temnejše, bolj rdeče in bolj modre. Barvanje z alkalnim ekstraktom zelenega čaja ni bilo tako uspešno kot z nevtralnim izvlečkom zelenega čaja. Pri barvanju z nevtralnim izvlečkom zelenega čaja in z uporabo čimže različnih molarnih koncentracij srebrovega nitrata so bili doseženi različni odtenki bombaža. Pri uporabi 50 mM AgNO 3 so bili doseženi zelo temni (skoraj črni) odtenki. Bombažni vzorci, pobarvani z nevtralnim izvlečkom zelenega čaja, so dosegli odlično UV-zaščito (50+), nekateri tudi po večkratnem pranju. Ključne besede: barvanje, zeleni čaj, čimžanje, srebrov nitrat, barve, UV-zaščita The Infl uence of Mordanting with Silver Nitrate on the Dyeability and UV Protection of Cotton Dyed with Green Tea Tekstilec, 2015, letn. 58(3), str. 191-198
doi:10.14502/tekstilec2015.58.191-198 fatcat:5air52dsynb3dlm7fopibnnauq