C
SECTION C — CHEMISTRY AND METALLURGY
  
METALLURGY
 C22
METALLURGY (of iron C21); FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS (production of metals by electrolysis or electrophoresis C25)
 C22B
PRODUCTION OR REFINING OF METALS (electrolytic C25C); PRETREATMENT OF RAW MATERIALS
 C22B

Note(s)

In this sub-class, groups for obtaining metals include obtaining the metals by non-metallurgical processes, and obtaining metal compounds by metallurgical processes. Thus, for example, group C22B 11/00 covers the production of silver by reduction of ammoniacal silver oxide in solution, and group C22B 17/00 includes the production of cadmium oxide by a metallurgical process. Furthermore, although compounds of arsenic and antimony are classified in C01B, production of the elements themselves is included in C22B, as well as the production of their compounds by metallurgical processes.


 C22C
ALLOYS (treatment thereof C21D, C22F)
 C22C

Note(s)

  1. In the absence of an indication to the contrary, in groups C22C 5/00-C22C 32/00 an alloy is classified in the last appropriate place.
  2. The term "based on" requires at least 50% by weight of the specified constituent or of the specified group of constituents. [2]

 C22D
( transferred to C22B 4/00, C25C )

 C22F
CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS