Sensitising natural wool with green and brown coffee using a facile extraction method to optimise dye process...

Area of Science:

• Textile Chemistry
• Natural Product Chemistry
• Dye Chemistry

Background:

• Green coffee powder, derived from raw coffee cherries, contains numerous potential components.
• Natural colorants are increasingly sought as sustainable alternatives to synthetic dyes.
• Wool fabric dyeing traditionally relies on various chemical dyes with environmental concerns.

Purpose of the Study:

• To extract a natural green colorant from green coffee powder using water.
• To optimize dyeing parameters for achieving a true and fast green tone on wool fabric.
• To compare the dyeing performance and color fastness of green coffee dye with brown coffee dye.

Main Methods:

• Water extraction of colorant from green coffee powder at room temperature for 24 hours.
• Exhaust dyeing method applied to wool fabric.
• Optimization of dyeing parameters including powder concentration, temperature, immersion time, and pH.

Main Results:

• Optimized dyeing parameters (2g powder, 100°C, 70 min, pH 6.7) yielded rich green hues with good tonal variation on wool.
• Both green and brown coffee dyes exhibited superior color fastness to washing.
• Good performance was observed for color fastness to light, rubbing, and perspiration for both coffee-derived dyes.

Conclusions:

• Green coffee powder serves as a viable source for an innovative natural green dye.
• The extracted green coffee dye exhibits remarkable dyeing properties and good color fastness on wool.
• This natural dye presents a new, sustainable option for the commercial textile dye market.