Perylene-Diimide Pigments

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) 

Popovic et al. (1987) studied photogeneration of N,N-bis(methyl)perylene-3,4,9,10-tetracarboxyldiimide by field modulation of the time-resolved fluorescence. The results show that the field increases the rate of decay of fluorescence but leaves the initial intensity unchanged. The results were described by a process which occurs by the field-assisted dissociation of the first-excited singlet state. The absence of quenching of the initial fluorescence (amplitude quenching) was interpreted as evidence that the photogeneration process cannot be described by Onsager theories. 

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Whenever the imide substituent in a perylene diimide pigment is greater than Cl, the preferred route to the pigment is by condensation of PTCA with a primary... 

Mixed Crystals and Solid Solutions of Perylene Diimide Pigments... 

FIGURE 18.4 A perylene molecule (a). The molecule on (b) is perylene diimide (PDI). The -NH group may be exchanged by other groups to obtain novel pigments with other hues and colors. 

Although not commercially available as pigments, the half imide/half anhydrides of PTCA (10), for example (11), are beginning to find academic and commercial interest, since they can be used to produce both unsymmetrical perylene diimides and perylene mono-imides (through decarboxylation) . ... 

Perylene pigments include the dianhydride and diimide of perylene tetracarboxylic acid along with derivatives of the diimide while perinone pigments are derived from naphthalene tetracarboxylic acid. 

The customary method of preparing perylene pigments is by reaction of perylene tetracarboxylic dianhydride with primary aliphatic or aromatic amines in a high boiling solvent. The dianhydride itself is also used as a pigment. Di-methylperylimide may also be obtained by treating the diimide with methyl chloride or dimethyl sulfate. 

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

Peroxyacetic acid. See Peracetic acid Peryflene maroon. See Pigment red 179 Perylene red Y. See Perylenetetracarboxylic anhydride 3,4,9,10-Perylenetetracarboxylic acid diimide. See Perylimide... 

Perylene pigments n. A group of vat pigments, nearly all of which are N,N -sub-stituted peryzene-3,4,9,10-tetracarboxylic diimides. Scarlet and vermilion varieties, resistant to bleeding, light, heat, and chemicals are used in plastics. 

Conversion of Perylenes Acenaphthene to Perylene Tetracarboxylic Acid Diimide (PTCI, Pigment Violet 29)... 

For the majority of perylene pigments, both color and stability properties derive from electronic pi-pi interactions. However, for Pigment Violet 29 (6), the unsubstituted diimide, hydrogen bonding between the imide hydrogens and the carbonyl groups is also possible, and is undoubtedly the reason for the added stability of this perylene pigment. 

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