Pigments fastness

Table 17 lists a number of commercially available pigments, along with their chemical structures, in order to illustrate the different structural types of Naphthol AS pigments. Fastness to solvents and migration resistance improve from top to bottom, i.e., with increasing number of CONH groups in the molecule. The first example, a simple (3-naphthol pigment, is the skeleton from which all other species are derived. 

Apart from their use as dyes and pigments, phthalocyanines are also being used as catalysts for oxidations, high temperature lubricants, semiconductors, and liquid crystals. Their robust chemical structures, which make them, as dyes and pigments, "fast" to light and heat stable up to 500 °C, means that phthalocyanines will find many more applications in the future. In a later part of this chapter, we shall see how phthalocyanines are being used as novel electrical conductors. 

Lord 660 A white pigmented, fast set modified acrylic adhesive for composite application. Offers the highest impact and peel strengths available in a room temperature curing system. 

Solvent Staining Scale for Pigments Fastness to Light Scale for Pigments... 

The reaction between phthalonitrUe and copper also takes place readily in feoihng quinoline or a-methyhiaphthalene the pigment is precipitated as fast as it is formed as a crystalline product. It is separated from the excess of copper by shaking with alcohol, when the metal sinks and the pigment, which remains in suspension, can be poured off the process may be repeated to give the pure compound. 

Uses. (9-Nitrochlorobenzene is used in the synthesis of azo dye intermediates such as o-chloroaniline (Fast YeUow G Base), i9-nitroani1ine (Fast Orange GR Base), o-anisidine (Fast Red BB Base), o-phenetidine, and (9-aminophenol (see Azo dyes). It also is used in corrosion inhibitors, pigments, and agriculture chemicals. -Nitrochlorobenzene is used principally in the production of intermediates for azo and sulfur dyes. Other uses include pharmaceuticals (qv), photochemicals, mbber chemicals (qv), and insecticides (see Insectcontroltechnology). Typical intermediates manufactured from the para isomer are -lutioaruline (Fast Red GC Base), anisidine, -aminophenol, -nitrophenol, -phenylenediamine, 2-chloro-/)-anisidine (Fast Red R Base), 2,4-dinitrochlorobenzene, and l,2-dichloro-4-nitrobenzene. 

Printing Inks. Printing ink preparation is similar to many coating systems. The resin is dissolved in the solvent, followed by pigment dispersion to produce the ink. In most printing operations, the solvent must evaporate fast for best production speed. Alcohol—hydrocarbon solvent combinations are used with polyamide resins for some printing processes (see Inks). 

In the same way acetoacetarulides and pyrazolones can be used as coupling components. Larger molecules can be formed in the pigment series by using a benzidine derivative as the middle component as, eg, in Vulcan Fast Red B [6358-87-8] (141) (Cl Pigment Red 38 Cl 21120). 

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