The dyeing industry is one of the most polluting industries globally. Use of eco-friendly products and processes can help reduce the pollution. Eco-friendly dyes are colourants derived from natural, non-toxic, and biodegradable sources. Unlike synthetic dyes, which are often made from petroleum-based chemicals, eco-friendly dyes come from plants, minerals, and even insects. Turmeric is known for its bright golden-yellow colour. It is derived from the root of the turmeric plant. Indigo gives blue colour and is derived from the leaves of Indigo plant. Madder is derived from roots of Rubia tictorum plant. It is used to give red colour on textile substrates in combination with alum. Cochineal is made from the cochineal insect and produces vibrant reds and pinks. Recycled dyes are extracted from coloured textile waste materials and industrial by-products. Supercritical CO2 dyeing uses pressurized carbon dioxide to dissolve and apply dyes. This waterless process is highly efficient and environment friendly.
Vat Dyes
The question asks to identify the class of dyes to which Indigo belongs. The provided passage discusses various eco-friendly dyes, including Indigo, noting it gives a blue colour and is derived from the leaves of the Indigo plant.
Indigo Dye Classification
While the passage details the source and colour of Indigo, it does not explicitly state its classification among dye types. However, based on established textile chemistry:
- Indigo is widely recognized as a prime example of a Vat Dye.
- Vat dyes are insoluble in water and are applied to fibres in a reduced, soluble 'leuco' form. After application, they are oxidized back to their insoluble form, becoming permanently fixed within the fibre.
- This classification aligns with the characteristics and application methods of Indigo.
Conclusion on Indigo Class
Therefore, Indigo belongs to the class of Vat Dyes.
Important Questions from Environmental pollution
Which one of the following is a major environmental issue in eastern Canada?
One of the main causes of air pollution in cities is emissions from vehicles like cars and trucks. Cars emit various pollutants which are bad for human health when inhaled, like
1) Nitrogen oxides (NO x)
2) Carbon monoxide (CO)
3) Carbon dioxide (CO 2)
4) Benzene
Which of the above pollutants are not tolerated by human beings even at very low levels?Which of the following substances are harmful for health if present in food items?
1) Pesticide residues
2) Lead
3) Metanil yellow
4) Mercury
Select the correct answer using the code given below:
Which of the commonly used household item(s) release Bisphenol A (BPA) which is an endocrine disruptor and bad for human health?
1. Steel utensils
2. Plastic coffee mugs
3. Aluminium utensils
4. Plastic water storage bottles
Select the correct answer using the code given below:Which one of the following is a cause of acid rains?
