Conditioning and Surface Treatment of Quinacridones

It is assumed that both radical ions interact through an electron transfer process, the system subsequently reverting to its original electronic state. A solid solution structure is essential for this type of synergistic interaction because both radical ions would need to be in relatively close proximity to each other. 

While some manufacturing processes for quinacridones directly deliver products that are fully pigmentary, most others, with the exception of products from the PPA process, require particle size reduction before commercial use. Generally, relatively large particle size pigments, which are more effective at light scattering, are opaque and relatively weak in tinted shades. Particle size reduction renders 

Quinacridone pigments are used primarily for decorative and functional effects. They provide a variety of colors, and contribute to long-term durability in a variety of systems. 

Artists colors utilize quinacridones because of demand for specific colors with long-lasting properties. More detailed information regarding applications of specific quinacridones is available in many commercial publications and in books devoted to pigment technology [69]. 

In addition, some quinacridones are found in unusual applications. For example, quinacridone and 2,9-dimethylquinacridone exhibit desirable photovoltaic properties [70], and display relatively high power conversion efficiencies in solar cell fabrication. Some quinacridones also have demonstrated reasonably good photoconductivity [71] and 2,9-dichloroquinacridone can function as a photoreceptor in electrophotography [72]. A variety of other atypical applications have also been claimed in the patent Uterature. 

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