For professionals in the chemical, manufacturing, and research sectors, a deep understanding of the properties of raw materials is fundamental to innovation and product development. Solvent Black 3 (CAS 4197-25-5) is a prime example of a dye whose chemical structure dictates its excellent performance across diverse applications. This article explores the science behind Solvent Black 3, detailing its molecular composition, physical characteristics, and how these attributes translate into its value as a high-performance dye. We also touch upon sourcing this essential chemical from a reputable manufacturer.

Molecular Structure and Chemical Identity

Solvent Black 3, also known as Sudan Black, is an azo dye with the chemical formula C29H24N6 and a molecular weight of 456.54 g/mol. Its IUPAC name is (2,2-dimethyl-1,3-dihydroperimidin-6-yl)-(4-phenylazo-1-naphthyl)diazene. The molecule features two azo (-N=N-) linkages, which are chromophores responsible for absorbing light and imparting color. It also contains complex aromatic and heterocyclic ring systems, including a perimidine moiety and a naphthyl group linked via azo bonds. The presence of methyl groups on the perimidine structure contributes to its solubility in non-polar organic solvents.

Physical and Chemical Properties in Detail

The utility of Solvent Black 3 is directly linked to its measurable properties:

  • Appearance: A fine black powder, indicating a solid state at room temperature.
  • Melting Point: Typically falls between 120-124 °C. This relatively low melting point is characteristic of many organic dyes and influences its processing in molten plastics or solvent systems.
  • Solubility Profile: Its excellent solubility in organic solvents like acetone (280 g/l), dichloromethane (116.8 g/l), and toluene (10.3 g/l) makes it a true 'solvent' dye, meaning it dissolves rather than disperses in the medium. This is crucial for applications where a clear, homogeneous color is required, such as in inks and transparent plastics.
  • Thermal Stability: Its heat resistance, up to 230°C in some tests, makes it suitable for melt processing in plastics like PS.
  • Light Fastness: A rating of 6 (on an 8-grade scale) signifies good resistance to photodegradation, ensuring color longevity.
  • Chromatism (△E): Values ≤1.0 suggest a very low color difference, indicating high color consistency.
  • Water Content and Ash Content: Low levels (≤1.0%) are indicative of a purified product.

Applications Driven by Properties

These properties directly enable its widespread use:

  • Plastics: Its solubility and heat resistance allow for deep, stable coloration in polymers during extrusion or injection molding.
  • Inks: Excellent solvent solubility ensures smooth flow and sharp definition in inkjet and writing inks.
  • Biological Staining: Its lipophilic nature allows it to stain fats and lipids effectively in histological preparations.

Sourcing Solvent Black 3: The Manufacturer's Role

Understanding the chemistry of Solvent Black 3 underscores the importance of quality control during its production. When you buy Solvent Black 3, selecting a manufacturer that adheres to strict synthesis and purification protocols is paramount. We, as a dedicated manufacturer, ensure the high purity and consistent properties of our Solvent Black 3, providing you with a reliable chemical for your research and industrial needs. Our commitment to quality control means you can trust the technical specifications and performance of the dye.

Conclusion

The scientific properties of Solvent Black 3, from its molecular makeup to its solubility and thermal stability, are what make it such a valuable and versatile dye. By understanding these scientific underpinnings, professionals can better leverage this chemical for optimal results. We invite you to contact us to purchase Solvent Black 3, request detailed technical data, or discuss how our high-quality dye can meet your specific application requirements.