| 摘要 |
<p>Process for coating objects by electrostatic spraying with enamel powder, the novelty being that, in spraying a cloud of any desired type of electrostatic powder coating, means are employed so the average specific resistance (ASR) of the cloud matches the requirements for good spraying. The means pref. provide an ASR high enough to ensure good electrostatic adhesion, but low enough to avoid counter-emission; and the coating thickness is pref. controlled by adjusting the ASR. The pref. means are (a) heating the fluidising air for the powder feed funnel(s) and possibly the carrier air; (b) mixing fresh powder with recycled powder, esp. using 30-50% fresh powder in the mixt. The powder coating obtd. have good adhesion, without crater formation.</p> |
