The Development and Trends of Disperse Dyes
The primary demand for dyes comes from the textile printing and dyeing industry, where the production volume of various fibers fundamentally determines the dye demand. For many years, natural fibers represented by cotton (which accounts for around 90% of natural fiber production) and chemical fibers represented by polyester have fundamentally dominated the development of dyes.
The primary demand for dyes comes from the textile printing and dyeing industry, where the production volume of various fibers fundamentally determines the dye demand. For many years, natural fibers represented by cotton (which accounts for around 90% of natural fiber production) and chemical fibers represented by polyester have fundamentally dominated the development of dyes.
With advances in the petroleum and polymer chemistry industries, synthetic fibers have rapidly developed, and the production volume of chemical fibers now far exceeds that of natural fibers. However, while cotton fiber shows weak growth, its production remains stable, resulting in little fluctuation in the demand for reactive dyes. According to current trend analysis, the demand for disperse dyes will continue to rise.
Disperse dyes were first produced by the German company Badische Anilin und Soda Fabrik in the 1820s, initially for dyeing acetate fibers. In the 1950s, the advent of polyester fibers (polyethylene terephthalate fibers, commonly known as polyester) led to rapid developments in disperse dyes, making them a pillar product of the dye industry. Disperse dyes are low molecular weight, water-insoluble, non-ionic dyes that utilize dispersants to suspend in dye baths, dispersing into the voids of polyester fiber macromolecules through intermolecular forces such as van der Waals forces and hydrogen bonds. However, their poor water solubility makes post-treatment difficult, requiring the addition of dispersants to stabilize their crystal form, ensuring they are highly dispersed in water before being used for high-temperature, high-pressure dyeing of polyester fibers.
Disperse dyes are specialized dyes for coloring polyester, suitable for the dense and water-insoluble structural characteristics of polyester. According to the "Comprehensive Guide to Dye Varieties," disperse dyes can be classified by chemical structure into azo, anthraquinone, nitro, methylene, coumarin, amino ketone, guanidine, sulfur indigo, benzofuran, benzodifuran, and thiazole categories. Among them, azo dyes account for about 64% while anthraquinone dyes make up about 25%. Azo disperse dyes can further be divided into monoazo, diazo, and heterocyclic azo dyes.
The trends in dye development can be summarized as follows:
1、Continuous Update of Dyes Based on Fiber Changes: Disperse dyes have developed in tandem with polyester fiber advancements.
2、Improvement Needs Based on Fiber Application Scenarios: As research on textiles deepens, many new and modified fibers are continuously being applied. Some of these new fibers present dyeing challenges, providing opportunities for disperse dye development.
3、Dominance of Azo Disperse Dyes: Azo disperse dyes are likely to maintain a dominant position for some time into the future, driven by their cost-effectiveness and performance.
4、Potential for Technical Breakthroughs with Heterocyclic Azo Disperse Dyes: There is potential to consider using high-yield and high-performance heterocyclic intermediates or derivatives from other fields in dye synthesis, effectively reducing costs.