DEPOSITION OF UNIFORM LAYER OF PARTICULATE MATERIAL

摘要

Deposition of particulate material of a substance on a surface includes: (i) charging a vessel with a compressed fluid; (ii) introducing into the vessel a first feed stream comprising a solvent and the substance and a second feed stream comprising the compressed fluid, wherein the substance is less soluble in the compressed fluid relative to its solubility in the solvent and the solvent is soluble in the compressed fluid, and wherein the first feed stream is dispersed in the compressed fluid, allowing extraction of the solvent into the compressed fluid and precipitation of particles of the substance; (iii) exhausting components from the vessel at a rate substantially equal to the rate of addition of such components to the vessel in step (ii) through a restrictive passage whereby a flow of particles of the substance is formed; and (iv) exposing a receiver surface to the exhausted flow of particles.