Acid Dyes — Properties, Applications & Product Range
The key property of acid dyes lies in their interaction with fiber polymers, leading to a strong bond between the dye and the material.
This happens through an ion-exchange mechanism, where ionic bonds form between the cationic groups in the fiber and the anionic dye molecules
(such as sulphonate groups). Along with ionic linkages, acid dyes may also bind through hydrogen bonding and Van der Waals forces,
ensuring excellent color strength and brilliance.
Applications
• Textiles: Wool, silk, nylon, polyamide, and modified acrylic fabrics
• Food Industry: Widely used as food colors
• Laboratories: Biological staining of basic proteins
• Other Uses: Leather finishing, wood coloring, paper, and cosmetics
Key Properties of Acid Dyes
• Highly soluble in water and in many cases, alcohol
• Anionic in nature – the dye anion is the active colored component
• Best suited for protein fibers (wool, silk), polyamides, and modified acrylics
• No affinity for cellulosic fibers like cotton (not suitable for cotton)
• Applied in acidic to neutral pH baths (commonly with sulphuric, acetic, or formic acid)
• Molecular weight typically ranges between 300–1000 g/mol
• Can be combined with basic dyes for shade development
• Form strong ionic, hydrogen, and Van der Waals bonds with fibers
• Generally decolorized when treated with reducing agents
• Provide bright shades with good light fastness and moderate wash fastness
Product Range
Our Acid Dyes are available in a wide spectrum of shades, delivering:
• Brilliant and vibrant colors
• Excellent solubility and consistency
• Reliable performance in textile, leather, food, and industrial applications
