Congo Red Direct Red 83 Analytical Grade
Congo Red (Direct Red 83) analytical grade is high-purity dye used as pH indicator (red at pH 3-5, blue above 5) and amyloid stain in microscopy. Despite lab use, classified as the synthetic organic coloring matter under HTS 3204.14.25.00. Supplied at 85% dye content minimum.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If basic dye like Basic Red 18 for lab use
Basic dyes are cationic; Direct Red 83 is anionic direct dye per chemical structure.
If diagnostic reagent kit component
Lab diagnostic reagents classify in 3822 regardless of dye base per use/function.
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Import Tips & Compliance
• Include intended use declaration; lab dyes still classify by chemistry, not end-use
• Restricted under Toxic Substances Control Act; pre-notice may apply for first import
• Batch certificates must specify CI 22120 to avoid generic 3204.19 classification
Related Products under HTS 3204.14.25.00
Direct Blue 86 Dye Powder
Direct Blue 86 is a synthetic organic azo dye in powder form, chemically defined as C32H22N6Na2O6S2, used for direct dyeing of cotton, wool, and paper without mordants. It falls under HTS 3204.14.25.00 as a specific direct dye listed in the tariff schedule. This water-soluble dye provides vibrant blue shades in textile and printing applications.
Direct Red 83 Textile Dye
Direct Red 83, also known as Congo Red, is a benzidine-based direct dye (C32H22N6Na2O6S2) for cotton and viscose fabrics, producing deep red shades. Classified under HTS 3204.14.25.00 due to its explicit listing as a direct dye preparation. Commonly used in historical textile dyeing despite modern toxicity concerns.
Direct Yellow 28 Dye Concentrate
Direct Yellow 28 is a stilbene-based direct dye (C34H24N2Na2O8S2) used for bright yellow shades on paper and textiles, soluble in water for exhaust dyeing. It qualifies for HTS 3204.14.25.00 as one of the named direct dyes in the schedule. Ideal for packaging and tissue paper coloration.
Kayaku Direct Blue 86 Liquid Preparation
Kayaku Direct Blue 86 is a liquid preparation based on Direct Blue 86 dye for continuous dyeing machines in textile mills. As a preparation specified in note 3 to Chapter 32 based on the named synthetic organic coloring matter, it falls under HTS 3204.14.25.00. Provides uniform blue dyeing on cellulosic fabrics.
Direct Yellow 28 Paper Dye Solution
Direct Yellow 28 solution for surface coloring of writing paper and packaging, containing 20% active dye in stabilized aqueous form. Meets HTS 3204.14.25.00 as preparation based on the specified direct yellow coloring matter per note 3. Provides lightfast yellow hues.