Spraying of liquids.

摘要

A coating is applied to a substrate by conveying the substrate past a number of liquid spraying nozzles (32) to which high voltage is applied to produce spray in the form of liquid ligaments which deposit as such, or in the form of droplets, on the substrate to form generally parallel tracks which merge with each other to produce a substantially uniform thickness coating. The nozzles (32) are operable in two modes: a normal spraying mode and a deflect mode in which the ligaments are deflected away from the substrate and towards a collector electrode (34). Operation of the nozzles (32) may be co-ordinated so that different formulations are deposited as separate panels in succession lengthwise of the substrate. The coating system is particularly suitable for coating multicoloured dyesheets for use in thermal transfer printing. <IMAGE>