extruders have the advantage of a very short fusion blending time so that they can be used for making large quantities of formulations which would be difficult to compound on a z blade mixer the cooled solid material can then be ground for example in a pin disk mill and sieved to obtain a powder of the desired particle size for example from 100 to 350 microns for use in a fluidized bed in an electrostatic fluidized bed or in with a flock gun or below 75 microns for electrostatic spraying or use in a cloud chamber coating powders based on epoxy resin compositions according to the invention can be applied to a variety of substances in particular metals such as steel and tin plate and can be cured by heating for example to temperatures between 150 u00b0 and 220 u00b0 c for various periods of time and provide smooth strong resistant coatings the invention is illustrated by the following illustrative embodiments parts therein are parts by weight components a 1 and a 2 were mixed in a reaction vessel with stirring and heated to the desired reaction temperature and kept at that temperature until low acid number of the product indicated essentially.