摘要 |
THE INVENTION OF PREPARING PARTICLES OF A SUBSTANCE, FOR EXAMPLE SELECTED FROM A FLAVOUR, FRAGRANCE, PIGMENT, DYE, BIOLOGICALLY ACTIVE COMPOUND OR A PLASTICS MATERIAL, COMPRISES CONTACTING THE SUBSTANCE OR A FORMULATION (WHICH MAY INCLUDE THE SUBSTANCE IN CONJUNCTION WITH A SECOND SOLVENT) WITH A FIRST SOLVENT WHICH COMPRISES A C₁-C₄ HYDROFLUOROCARBON, ESPECIALLY TETRAFLUOROETHANE, AND SUBJECTING THE RESULTANT MIXTURE TO BE SPRAYED AS A MIST (14) FROM A HIGH PRESSURE ENVIRONMENT IN A FIRST VESSEL (2) TO A LOW PRESSURE ENVIRONMENT IN A SECOND VESSEL (8), THEREBY TO CAUSE SEPARATION OF AT LEAST SOME OF THE SUBSTANCE FROM THE FIRST SOLVENT AND THE FORMATION OF FINE PARTICLES (20) OF THE SUBSTANCE.(FIG 1)
|