Drum coating techniques

Organic photoreceptors are prepared by solvent coating techniques and can be fabricated in a drum or web configuration. These can be prepared in the single- or dual-layer arrangement. In the dual-layer arrangement, the generation... 

Stationary phases are divided into the same two groups as the techniques in this chapter paper and thin layers. The paper can be used unsupported, but the thin layers need to be coated on carriers such as glass, aluminum, or plastic. A variety of shapes can be used for the bed in addition to the conventional rectangular shape. Some are circles, wedges, cylinders, rods, and even drums. Thin layers are more flexible and more popular, so they are treated in more detail. 

The MI technique is also based on cold-trapping of the GC eluates, but differs from DD in the addition of 1-2% of an inert matrix gas (typically argon) to the carrier gas. The effluent stream is sprayed onto the surface of a slowly rotating, gold-coated drum at a temperature of about... 

Recently, Rounsley [88] reported a 5 to 18% increase in the drying rates of paper and coatings in the presence of a nonuniform, static, electric field. This technique has been tested for both felted and unfelted drum drying as well as air impingement and radiant drying. If commercially successful, this concept has the advantage of fast response and may be used for moisture profile control. 

Japanese lacquer trays from the Momoyama period of Japan, show the influence of the Zen culture, the simplicity of the neguro technique of applying the lacquer. Numerous items of these periods, which include trays all sorts of containers and boxes, even tea pots, sake containers, musical instruments like drums and stirrups were coated with Japanese lacquer. Figure 8 [9] shows a box from the Iate18th century and early19th century. For the decorations of such items as boxes, gold and silver flakes were incorporated when the last few layers of lacquers, but before the final topcoat, were applied. As indicated earlier, fine lacquer ware may have as many as 30-40 layers of thin coating of oriental lacquer. 

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