4-Phenylbenzophenone, identified by its CAS number 2128-93-0, is a pivotal organic compound within the specialty chemicals sector, primarily recognized for its role as a Type II photoinitiator. Its unique chemical structure and properties lend themselves to a variety of industrial applications, most notably in UV-curable systems. Understanding its chemical nature and application scope is crucial for formulators and procurement managers seeking high-performance materials.

Chemical Profile of 4-Phenylbenzophenone

At its core, 4-Phenylbenzophenone is a derivative of benzophenone, featuring a phenyl group attached to the para position of one of the phenyl rings of benzophenone. Its molecular formula is C19H14O, and it possesses a molecular weight of approximately 258.31 g/mol. Key physical properties include:

  • Appearance: Typically an off-white to white crystalline powder.
  • Melting Point: Generally falls within the range of 99-103 °C, indicating a stable solid state at room temperature.
  • Purity: High-purity grades, often exceeding 99%, are readily available from manufacturers, ensuring reliable performance.
  • Solubility: Soluble in many organic solvents, which facilitates its incorporation into various liquid formulations.
  • UV Absorption: It exhibits specific UV absorption characteristics, typically in the UVA and UVB regions, making it effective for initiating photochemical reactions under UV light.

Industrial Applications Driven by its Properties

The primary industrial application of 4-Phenylbenzophenone is as a photoinitiator in UV-curable coatings, inks, and adhesives. Its function in these systems is to absorb UV radiation and subsequently generate free radicals, which then initiate the polymerization of monomers and oligomers. This leads to rapid hardening or curing of the applied material.

The compound's specific attributes make it particularly valuable for:

  • UV-Curable Coatings: Essential for wood varnishes, metal coatings, and clear coats, providing durability and fast drying times.
  • Printing Inks: Used in various printing processes, including screen printing and packaging inks, where its low-odor nature is a significant advantage, especially for food contact applications.
  • Adhesives: Facilitates the UV curing of adhesives used in electronics, medical devices, and assembly applications.
  • Photo-resists: Its light-sensitive properties can also be leveraged in the formulation of photo-resists used in microelectronics manufacturing.

Sourcing and Procurement Considerations

For industries requiring 4-Phenylbenzophenone, reliable sourcing is critical. When planning to purchase this chemical, it is important to connect with established manufacturers and suppliers. Companies that offer competitive pricing and ensure consistent product quality are preferred. Many chemical suppliers in China and globally provide this compound, often with options for bulk orders. Understanding lead times and availability from your chosen manufacturer is also a key aspect of procurement.

Conclusion

4-Phenylbenzophenone (CAS 2128-93-0) is a fundamental component in many UV-curing applications due to its effective photoinitiation capabilities and beneficial physical properties, including its low odor. Its widespread use in coatings, inks, and adhesives underscores its importance in modern manufacturing. By understanding its chemical characteristics and actively seeking out reliable suppliers, businesses can effectively leverage this material to enhance their product offerings and production efficiency.