Novel Azo dyes containing a hydrazide-hydrazone moiety for dyeing polyester fabric

Area of Science:

• Organic Chemistry
• Textile Chemistry
• Materials Science

Background:

• Azo dyes are crucial for textile coloration.
• Benzothiazole derivatives offer unique chromophoric properties.
• Dispersed dyes are vital for synthetic fiber dyeing, particularly polyester.

Purpose of the Study:

• Synthesize novel azo dyes incorporating hydrazide-hydrazone and benzothiazole moieties.
• Determine optimal dyeing parameters (temperature, pH, time, shade) for polyester.
• Evaluate the color strength, hue, and fastness properties of the synthesized dyes.

Main Methods:

• Chemical synthesis of novel azo dyes.
• Polyester dyeing experiments under varied conditions.
• Spectrophotometric analysis for color strength (K/S) and colorimetric coordinates (CIEL*a*b*).
• Assessment of light, washing, and crocking fastness.

Main Results:

• Effective synthesis of azo dyes containing hydrazide-hydrazone linked to benzothiazole.
• Identified optimal dyeing conditions for specific dyes: Dye 4 (30 min, pH 8, 110°C, 3% shade) and Dyes 10/11 (30 min, pH 2, 130°C, 3% shade) achieved excellent color strength (K/S=26).
• Polyester fabrics dyed in hues ranging from beige to dark brown.
• Substituent effects on color strength and colorimetric properties were analyzed.
• Dyes exhibited very good color strength and exceptional fastness properties.

Conclusions:

• The synthesized benzothiazole-based azo dyes are effective for polyester dyeing.
• These dyes provide a range of stable hues with excellent color strength.
• The dyes demonstrate superior fastness to light, washing, and crocking, making them suitable for textile applications.