Roll coating rollers

Roller coating Roller-hearth furnace Roller nulls Roller printing Rollin film Rolling Roll nulls... 

Two methods of plastisol coating are shown in Figure 2 depending on whether a flat surface (using a knife-on-roller method) or even-thickness coating (reverse roll coating) is required. 

All of the previously mentioned techniques involve coating the MPL on top of a substrate, such as the DL or the membrane [125]. However, the MPL can also be made out of a carbon-based polymer porous sheet that is simply placed between the CL and DL when assembling the fuel cell [129,140-142]. The sheet-based MPL approach is not as common and is not widely used. In fact, in previous years a commercially based MPL film was available (Carbel MP, W. L. Gore Associates, Inc.) but is now no longer manufactured. Shi et al. [140] prepared an MPL sheet using a two-roll-shaft roller to roll a mixture of carbon black and PTFE repeatedly. Once the desired toughness in the film was achieved, it was sintered. This MPL sheet performed well, especially under high-humidification conditions. 

Roll coating is widely used for uniform, whether flat or cylindrical, surfaces including fiber bundles. In a roll coating process, fibers are coated between two rollers, an applicator roller and a backup roller coating is fed continuously to the applicator roller by a feed roller which runs partially immersed in a coating bath and the backup roller pulls the fibers by rotating in opposite directions. Slow... 

Covering metallic shafts, rolls and rollers with rubber is required for many applications such designs are used in the textile, printing, and many other industries. For producing coatings, molds with a vertical axis are often filled through inlet holes located along the diameters of the mold... 

For the coating of continuous substrates, such as flooring, wall covering and tarpaulins, direct or transfer coating is used. The paste can be applied directly using knife on roller or belt, or indirectly via reverse roll coating. The substrate can be a carrier material which is removed later. This process permits multilayer... 

For the above reasons, processes that involve combinations of heat and pressure are the most widely used. This is normally accomplished by hot-roll pressure devices in which at least one roll is heated with a quartz lamp (Lee, 1975 Prime. 1983 Kuo. 1984 Hiraoka et al.. 1993). Offset of the toner to the fuser roll can be avoided by the use of special oils wicked onto the surface of the roll. Most roller fusing devices use heated rolls coated with silicone or fluorocarbon elastomers. Composite layer structures with multiple layers for improved process lifetime are becoming more common. Figure 17 shows a cross-section of a typical fuser roller and Fig. 18 shows a typical fusing process. For a review of fusing materials, see Gruber et al. (1989). For a discussion of the effects of paper properties on fusing, see Sanders et al. (1996). 

The most common methods of paint applications are brush and roller, air or airless spray, roll coating, electrostatic spraying, electro deposition, and dip coating. Many factors affect the choice of method to be used for a particular application. These include film thickness, appearance requirements, and operating cost. 

Direct roll coating method is used for coating thin-gauge sheets or coil stock. The sheet stock is fed between applicator rollers rotating in the same direction as the moving sheet. The apphcator rollers are fed by smaller pick-up rollers that are partially immersed in trays containing the paint. The coat sheet is subsequently fed into an oven for baking. 

A coating may be achieved by passing the ply between a coating roller and a back-up roll (usually rubber) or by kiss coating whereby the tensioned web makes contact with a coating roller. With certain more difficult materials a nip roll system (hot or... 

Chatter n. Transverse roll marks on roll coat-painted strip with varying film thicknesses, which are usually due to roll coater vibration or a non-concentric roller. 

Reverse-roll coating n. A method of coating wherein the coating material is premetered between two rolls, one of which deposits the coating on a substrate. The thickness of the coating is controlled by the gap between the rollers and also by the speed of rotation of the coating roll. 

Tensioning systems. In the systems discussed until now, the coating resulted from a mere contact with the coating roller. Usually tension rolls are added as... 

Here the adhesive runs down to the coating roller due to gravity and adhesion to the rolls. Therefore, the adhesive should not be too fluid or else it could run down too fast. These systems are used when the viscosity is within a range of 5000-50,000 mPas. 

Complete the edges of only one wall area and make the switch to rollers. This will help ensure your detail work is still wet when you apply the first rolled coat. 

With reverse roll coating, the gap between a metering roller and applicator (casting) roller determines the amount of coating transferred to the applicator roll. The coating is transferred to the substrate as the substrate passes between the applicator roll and a support (back-up) roll. 

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