Dyes, examples important properties

Attention must also be focused on the noncrystalline domains. Many important properties of fibers can be directly related to these noncrystalline or amorphous regions. For example, absorption of dyes, moisture, and other penetrants occurs in these regions. These penetrants are not expected to diffuse into the crystalline domains, although there may be adsorption on crystaUite surfaces. The extensibUity and resUience of fibers is also directly associated with the noncrystalline regions. 

Special additives are often included in a carrier formulation to provide specific properties such as foam control, stabiUty, and fiber lubrication during dyeing. Most important are the solvents used to solubilize the soHd carrier-active chemicals. These often contribute to the general carrier activity of the finished product. For example, chlorinated benzenes and aromatic esters are good solvents for biphenyls and phenylphenols. Flammable compounds (flash point below 60°C) should be avoided. 

Electric field sensitive dyes respond to changes in electrical membrane potential by a variety of different mechanisms with widely varying response times depending on their chemical structure and their interaction with the membrane. An understanding of the mechanisms of dye response and their response mechanisms is important for an appropriate choice of a probe for a particular application. The purpose of this chapter is, therefore, to provide an overview of the dyes presently available, how they respond to voltage changes, and give some examples of how they have been applied. Finally, because there is still scope for the development of new dyes with improved properties, some directions for future research will be discussed. 

In this chapter, we describe the design and important properties of supra-molecularly organized dye molecules in the channels of hexagonal nanocrystals. We focus on zeolite L as a host. The principles, however, hold for other materials as well. As an example, we mention ZSM-12 for which some preliminary results have been reported [55], We have developed different methods for preparing well-defined dye-zeolite materials, working for cationic dyes, neutral dyes, and combinations of them [3, 22, 25, 52], The formula and trivial names of some dyes that so far have been inserted in zeolite L are reported in Section II.C. The properties of natural and commercially available zeolites can be influenced dramatically by impurities formed by transition metals, chloride, aluminiumoxide, and others. This fact is not always sufficiently taken care of. In this chapter, we only report results on chemically pure zeolites, the synthesis of which is described in [53]. 

The important property of these compounds is that they will couple with aromatic amines and hydroxy derivatives to form highly coloured products which, when rendered soluble by sulphonation, give rise to a great range of dyestuffs known as the azo dyes. A simple example of a coupling reaction is shown in the following equations ... 

Of course, advances are expected, merging important properties, for example, the utilization of NIR dyes in the harvesting of the solar energy aiming the enhancement of the efficiency of solar cells. Lanthanides upconversion is efficient and visible to the naked eye, provided that powerful excitation sources are used. Infrared light from the sun can hardly lead to observation of visible photons via upconversion. The efficiency of the process is indeed very low [130]. 

CAPB has excellent dye transfer inhibition properties. This snrfactant can be used in laundry detergent formulas, where mildness and dye transfer inhibition are important performance criteria. The formulated blends A through E can act as starting-point formulation guidelines for such products. Fine-fabric washes and laundry prespotters can also be formulated using these blend compositions as starting point. Examples of the finished laundry product formulations are in Tables 29 through 34. 

Anthrimides. Despite the facts that anthrimides have excellent leveling properties and cover a wide range of colors from yellow to black, they have htde commercial importance because of their duller shades and lower tinctorial strength. However, the anthrimides are important intermediates for manufacturing anthrimidocarbazoles. Some examples of anthrimide dyes are Cl Vat Orange 20 [6370-69-0] (149), (Cl 6302S), Cl Vat Violet 16 [4003-36-5] (150) (Cl 65020] Cl Vat Black 28 [128-79-0] (151) (Cl 65010] and Cl Vat Red 48 [4478-06-2] (152) (Cl 65205) (Fig. 6). 

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