Indigo Market and Craft Development
Indigo, an ancient dye, still holds an important position in modern industry. It is mainly used for denim dyeing, with more than 90% of global indigo dye used in jeans production.
1. Global Market Overview
After BASF realized industrial synthesis in 1897, chemical indigo gradually replaced natural products. The global market size reached USD 603.2 million in 2021 and is expected to increase to USD 1.1226 billion by 2028, with a compound annual growth rate of over 9%.
Currently, more than 99% of indigo is produced through chemical synthesis, among which denim dyeing accounts for over 80%, with an annual demand of approximately 80,000 tons.
2. Upstream and Downstream Industry Chain Analysis
1. Upstream Raw Material End
The core raw materials for synthetic indigo include aniline, hydrogen cyanide, formaldehyde, etc. Among them, 80% of hydrogen cyanide is produced by the Andrussow process, and the raw materials depend on natural gas, ammonia and air.
2. Midstream Production End
The mainstream processes are divided into chemical synthesis and biological fermentation. The chemical method mainly adopts the anilinoacetonitrile route, while the biological method produces indigo through Escherichia coli fermentation, which can reduce wastewater discharge by 50%.
3. Downstream Application End
More than 90% of indigo is used for denim dyeing, promoting the development of denim products towards light weight and multi-color systems, and extending to categories such as jackets and backpacks. In 2021, the global demand for indigo in denim clothing accounted for 82% of the total output.
3. Evolution of Production Technology and Process
Chemical Synthesis Method
It is the current mainstream production process, accounting for as high as 99%. Since BASF successfully developed the indigo synthesis technology in 1897, the technology has undergone multiple technical optimizations and improvements.
Plant Extraction Method
Plant indigo, as a natural reduced dye derived from plants, has a history of more than 3,000 years, but it accounts for a small proportion in modern industrial production.
Plant Indigo Preparation Process:
- Biotransformation: Converting indoxyl glycosides in indigo plants into indoxyl through microbial fermentation
- Oxidation Reaction: Indoxyl is oxidized to form indigo under alkaline conditions
- Refining Treatment: Obtaining refined indigo suitable for textile dyeing
In recent years, biotransformation preparation and in-situ dyeing technology have become research hotspots, providing new ideas for the biological preparation of textile pigments and the dyeing process of biomass pigments.
4. Core Production Technology: Breakthroughs and Advantages of the Andrussow Process
The Andrussow process uses natural gas, ammonia, and air as raw materials to synthesize hydrogen cyanide, which is then added with formaldehyde to generate glycolonitrile (a key intermediate for indigo).
Combining its own technological advantages, Donggeng Company has carried out brand-new process optimization and improvement in terms of reaction, deamination, and preparation based on the Andrussow process route, and has developed the world's new generation of hydrogen cyanide and its derivative synthesis process technology.
5. Industry Development Trends
1. Technological Upgrading
The combination of the Andrussow process and electrochemical reduction technology can reduce the usage of sodium dithionite. It is expected that the environmental protection cost will decrease by another 15% by 2030.
2. Regional Transfer
The raw material bases in Northwest China continue to expand, and it is expected that the Asia-Pacific market share will exceed 60% by 2031.
3. Product Diversification
Bio-based indigo is extending to the food and pharmaceutical fields, and the market size growth rate may be twice that of the chemical method.