This sub-class deals with the making of moulds for casting metals or of other refractory moulds. It embraces selection and preparation of materials therefor and also the necessary patterns, processes, machines, accessory devices or tools.
The term "metallic powder" is to be understood as covering powders containing a substantial proportion of non-metallic material.
The term "powder" is not intended to exclude somewhat larger particles which are worked, obtained or behave in a manner similar to powder, e.g. fibres.
The production of metal powder is classified in this sub-class insofar as the invention relates to the preparation of powder with specific physical characteristics. [3]