The world of color is intricately linked to the precise chemistry of dyes. For manufacturers striving to create vibrant and durable colorants, the quality of raw materials is of utmost importance. Sodium 2-Naphthol-7-Sulfonate, with CAS number 135-55-7, stands out as a key intermediate in the synthesis of many important dyes, particularly azo dyes. Understanding its properties and how to source it effectively can be a significant advantage for any company in the color industry.

What is Sodium 2-Naphthol-7-Sulfonate?
Also known as F Acid, this compound is a naphthalene derivative characterized by a hydroxyl group and a sulfonic acid group, supplied as sodium salt. Its chemical structure makes it a versatile building block. It typically presents as an off-white powder with a purity assay of 98% minimum, although higher purities are often available. For those looking to buy this intermediate, understanding its role is key to appreciating the need for reliable sourcing from chemical manufacturers.

Functionality in Dye Production
Sodium 2-Naphthol-7-Sulfonate is a crucial coupling component in the synthesis of azo dyes. The azo group (-N=N-) is formed through a diazotization reaction, and this intermediate then couples with the diazonium salt. The resulting molecule's chromophore—the part of the molecule responsible for color—is determined by the specific structure of both the diazonium component and the coupling component like CAS 135-55-7. The presence of the sulfonic acid group (-SO3Na) imparts water solubility to the final dye, which is a vital property for many dyeing processes, especially for natural fibers like cotton and wool.

Manufacturers of textile dyes, printing inks, and pigments rely heavily on the consistent quality of such intermediates. Variations in purity or the presence of unintended by-products can lead to duller shades, poor color fastness, or inconsistent dyeing results. Therefore, selecting a supplier that guarantees high purity and stable properties is essential for maintaining product integrity and customer satisfaction.

Why Reliable Sourcing Matters
For any industrial buyer, from a small batch producer to a large-scale dye manufacturer, ensuring a stable and high-quality supply of Sodium 2-Naphthol-7-Sulfonate is critical. When you search for a manufacturer or supplier, consider:

  • Quality Assurance: Confirm that the supplier provides detailed specifications and Certificates of Analysis. For CAS 135-55-7, a purity of 98% min is a common benchmark.
  • Production Capacity: Ensure the supplier can meet your volume requirements, especially if you are planning for scaled production.
  • Lead Times and Logistics: For time-sensitive projects, understanding delivery times (e.g., 5-7 days) and packaging options (e.g., 25kg drums) is important.
  • Technical Support: A responsive supplier who can answer technical queries or assist with product documentation can significantly simplify the procurement process.

Conclusion
Sodium 2-Naphthol-7-Sulfonate is more than just a chemical; it's a foundational component for creating the colors that enrich our world. By understanding its role in dye synthesis and focusing on sourcing from reputable manufacturers, businesses can ensure the quality and vibrancy of their finished products. If you are looking to purchase this intermediate, partnering with a trusted supplier will be key to your success in the competitive colorants market.