Peiylene diimides

Peiylene diimides are diimides of perylene-3.4.9,10-tetracarboxylic acid. The use of these materials as generation layers has received considerable emphasis in the past two decades. See, for example, Schlosser (1978), Graser et al. (1983), Khe et al. (1984), Borsenberger et al. (1986, 1986a), Staudenmayer and Regan (1988), Loutfv et al. (1989), Duff et al. (1990), and Kitamura et al. (1991). This work is discussed separately in Chapter 10. 

Popovic et al. (1985) investigated photogeneration of a series of peiylene diimides by delayed-field and field-induced fluorescence quenching techniques. The results for N.N-bis(phenyl)perylene-3,4.9.10-tetracaiboxyldiimide (PPECI)... 

Molecular complexes, such as the complex formed between poly(N-vinylcaibazole) and 2,4,7-trinitro-9-fluorenone, and dye-polymer aggregates were widely used as generation materials in many early applications. Since these materials are not infrared sensitive, there has been increasing emphasis on pigments. The more widely studied are various azo, phthalocyanine, squaraine, and peiylene diimide derivatives. A common feature of all of these materials is that they are polymorphic and exist in many different crystal forms. The properties are thus very sensitive to the conditions used in their preparation. Further, the sensitivity of these materials is strongly field dependent as well as dependent on the transport material. For a review of generation materials, see Law (1993). 

In the example shown in Figure 5, four BODIPYs were covalently attached to the peiylene diimide core. In accordance with the increase in BODIPY number on the structure, extinction coefficient of the molecule at BODIPY s maximum absorbance wavelength (526 ran) increases dramatically to 250000M cm . Energy transfer efb-ciency was determined to be 99% with a critical Forster radius of 4.7 ran. In the second example shown in Figure 5, enhancement in emission of the core distyryl-BODIPY was observed as the number of terminal BODIPY donors was increased, as expected. ... 

Peiylenes. Perylene pigments are either the 3,4,9,10-tetracarboxylic dianhydride or more often N,NT-substituted diimides (Table 7). 

---