Method of preparing finely divided polyamides

Claim 1

THE PROCESS OF PRODUCING A FINELY DIVIDED SYNTHETIC LINEAR POLYAMIDE WHICH COMPRISES FORMING A MIXTURE OF SAID POLYAMIDE AND A SOLVENT, PLACING SAID MIXTURE IN A CLOSED, SUBSTANTIALLY OXYGEN-FREE SYSTEM, HEATING SAID MIXTURE UNDER SUPERATMOSPHERIC PRESSURE TO A TEMPERATURE ABOVE THE BOILING POINT OF SAID SOLVENT SUFFICIENT TO DISSOLVE SAID POLYAMIDE, COOLING SAID MIXTURE TO PRECIPITATE SAID POLYAMIDE IN THE FORM OF FINEY DIVIDED PARTICLES AND REMOVING SAID SOLVENT, SAID SOLVENT BEING A MIXTURE CONSISTING OF AT LEAST 5% WATER BY VOLUME, AND A SATURATED ALIPHATIC ALCOHOL HAVING ONE TO FIVE CARBON ATOMS, SAID POLYAMIDE BEING ONE WHICH IS SOLUBLE IN PHENOL AND INSOLUBLE IN LOWER SATURATED ALIPHATIC ALCOHOLS BELOW THEIR BOILING POINT AT ATMOSPHERIC PRESSURES, AND BEING ONE WHICH ON HYDROLYSIS WITH HYDROCHLORIC ACID YIELDS MATERIAL SELECTED FROM THE GROUP CONSISTING OF (A) AMINO ACID HYDROCHLORIDES; (B) MIXTURES OF DIAMINE HYDROCHLORIDE AND DIBASIC CARBOXYLIC ACID; AND (C) MIXTURES OF AMINO ALCOHOL HYDROCHLORIDE AND DIBASIC CARBOXYLIC ACID.