Question

Which of the following dyes are more prone to gas fading?

• A. reactive dyes
• B. disperse dyes
• C. acid dyes
• D. vat dyes

Hint:

Disperse dyes (especially on acetate) are the most prone to gas fading due to the chemical structure of some of the dyes used in this class.

Answer 1

The Correct Option is B

Step 1: Understanding Gas Fading: Gas fading is a type of color change that occurs in dyed textiles due to exposure to atmospheric pollutants, primarily oxides of nitrogen (NOx). These pollutants can react with certain dyes, causing them to fade or change color. 
Step 2: Dye Types and Gas Fading Susceptibility: Disperse Dyes: Some disperse dyes, particularly those used on acetate and sometimes on nylon and polyester, are highly susceptible to gas fading. The chemical structure of certain anthraquinone-based disperse dyes makes them vulnerable to NOx attack. 
Reactive Dyes: Reactive dyes form strong covalent bonds with the fiber and are generally resistant to gas fading. 
Acid Dyes: Acid dyes are used on protein fibers (wool, silk) and nylon. Their susceptibility to gas fading varies, but they are generally less susceptible than disperse dyes on acetate. 
Vat Dyes: Vat dyes are known for their excellent fastness properties, including high resistance to gas fading.