Anthraquinone Azo Dye Composition for High-Temperature Light Fastness

The patent applies parameter changes by modifying the chemical structure of the dye molecules, specifically incorporating cyano groups at positions 5 and 8 of the anthraquinone nucleus, and using specific coupling components with electron-withdrawing groups. These structural parameter changes result in dyes that maintain excellent light fastness (grade 5-7) even under high temperature conditions (up to 200°C thermofixing), resolving the contradiction between achieving adequate light fastness and maintaining it at elevated temperatures.

The patent achieves universality by developing a series of dyes based on the same core structure (1,4,5,8-substituted anthraquinones with cyano groups) that can produce multiple shades from golden-yellow to orange by varying only the coupling component. This allows single-dye applications with excellent build-up capacity (up to 70% exhaustion) while maintaining shade variety, eliminating the need for complex dye mixtures that would compromise build-up performance.

The patent applies composite material principles by creating complex molecular structures that combine multiple functional groups: the anthraquinone chromophore for colour strength, cyano groups at positions 5 and 8 for fastness properties, and specifically designed coupling components (such as pyridone derivatives with electron-withdrawing groups) for migration resistance. This composite molecular architecture achieves both intense colouration (exhaustion up to 70%) and excellent fastness to migration (grade 5-7), resolving the contradiction between tinctorial strength and migration fastness.