| abstract |
2084185 9118682 PCTABS00008 A process and apparatus for directing coating materials at a substrate with reduced production of mist and enhanced range of coating thickness and uniformity of coverage. A flow of coating liquid or fluid (821) is directed toward a substrate, and attenuated (826) in transit by a co-flowing impingement fluid (823). The impingement fluid is capable of attenuating liquid in the coating stream into droplets that form a fine mist (827). The mist is propelled toward the substrate (826) by the impingement fluid and deposited on the substrate. The aqueous liquid is preferably less than 100 ·C, and directed through an outlet under a low pressure, for example, less than 12 psi (82 kPa, such that the liquid velocity is low (e.g. less than 1 meter/second). Process parameters may be varied to reduce grainy or streaky coatings, thereby assuring thorough coverage of a substrate even with very thin coatings. |