Power preconditioning for electrostatic application

Claim 1

In the process for applying organic hygroscopic powder to coat a preheated glass container wherein said powder is electrostatically applied to said glass container in a powder application station and the adhered powder is subsequently thermally fused on said glass container to form a smooth coating, the improvement wherein said hygroscopic powder is preconditioned in a preconditioning zone prior to electrostatic application to said glass container by passing a stream of dry, inert gas having a dew point of less than about 35° F. upwardly through a mass of said powder at a rate sufficient to suspend said powder in said stream as a fluidized bed and mechanically agitating said fluidized bed for a residence time sufficient to yield a substantially dry, free flowing powder, separating the free flowing powder from said stream by aspirating through an outlet disposed intermediate of open ends of a vertical conduit immersed in said bed, and then transferring said free flowing powder to the electrostatic application station.