Patent ID: 6918963

Claim:
An apparatus for manufacturing commercial quantities of zinc sulfide-based electroluminescent phosphor having a moisture resistant coating thereon, said apparatus comprising: a reaction vessel having a given height and a porous disc at the bottom thereof; a supply of phosphor particles within said vessel; a first supply of an inert gas for fluidizing said particles, said first supply of inert gas entering said vessel through said porous disc; a heater surrounding said reaction vessel for heating said reaction vessel to a reaction temperature; a supply of a coating precursor; first means for conducting said coating precursor from said supply to said reaction vessel, said first means entering said reaction vessel at said bottom of said vessel at a position above said porous disc; a supply of a co-reactant; and a second means for conducting said co-reactant from said supply to said reaction vessel, said second means entering said reaction vessel at a position substantially mid-way of said given height.