Method of preparing coating materials

A method of producing coating powders comprising the steps of:

• (A) providing a first vessel having a motor driven mixer;
• (B) providing a second vessel;
• (C) providing a source of supercritical CO.sub.2 gas;
• (D) charging such first vessel with starting materials consisting essentially of a polymeric resin and a curing agent both of which are solid at room temperature, such first vessel being substantially free of any solvent that is capable of dissolving such polymeric resin to any appreciable degree at 23.degree. C. and 1 atmosphere;
• (E) supplying such supercritical CO.sub.2 gas to such first vessel, such that such first vessel contains from about 10 percent by weight to about 90 percent by weight such CO.sub.2 gas and from about 10 percent by weight to about 90 percent by weight such starting materials;
• (F) mechanically mixing such starting materials and such supercritical CO.sub.2 gas in such first vessel utilizing such mixer for a period of from about 1 minute to about 480 minutes;
• and
• (G) transferring such mixture of such CO.sub.2 gas and such starting materials from such first vessel through a header and into such second vessel, such header comprising multiple nozzles having an orifice diameter of from about 0.01" to about 1", such second vessel being maintained at an internal pressure of from about 0 psi to about 5000 psi and a temperature of from about -85.degree. C. to about 200.degree. C. during said transferring step.