C
SECTION C — CHEMISTRY AND METALLURGY
 C

Note(s)

Definitions for Section C:

  • Alkali metals: Li, Na, K, Rb, Cs, Fr
  • Alkaline earth metals: Ca, Sr, Ba, Ra
  • Lanthanides: elements with atomic numbers 57 to 71 inclusive
  • Rare earths: Sc, Y, Lanthanides
  • Actinides: elements with atomic numbers 89 to 103 inclusive
  • Refractory metals: Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, W
  • Halogens: F, Cl, Br, I, At
  • Noble gases: He, Ne, Ar, Kr, Xe, Rn
  • Platinum group: Os, Ir, Pt, Ru, Rh, Pd
  • Noble metals: Ag, Au, Platinum group
  • Light metals: alkali metals, alkaline earth metals, Be, Al, Mg
  • Heavy metals: metals other than light metals
  • Iron group: Fe, Co, Ni
  • Non-metals: H, B, C, Si, N, P, O, S, Se, Te, noble gases, halogens
  • Metals: elements other than non-metals
  • Transition elements: elements with atomic numbers 21 to 30 inclusive, 39 to 48 inclusive, 57 to 80 inclusive, 89 upwards

  
METALLURGY
 C25
ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR (electrodialysis, electro-osmosis, separation of liquids by electricity B01D; electrolytic machining B23P; electroless, i. e. chemical, plating C23C; anodic or cathodic protection C23F; electrolytic production of single crystals C30B; electrochemical methods of analysis G01N; electrochemical measuring, indicating or recording devices G01R; electrolytic circuit elements, e.g. capacitors, H01G; electrochemical current or voltage generators H01M)  [2]
 C25

Note(s)

  1. Inventions dealing with electrolytic or electrophoretic processes and apparatus or operational features are classified (a) under the groups for the compounds or articles produced, and (b) under the groups provided for the apparatus or operational features. [2]
  2. The electrolytic or eletrophoretic purification of liquids is classified in the classes appropriate to the nature of the liquid, e.g. A01K 63/00, C02F 1/46, C25B 15/08, C25D 21/16, C25F 7/02[2]
 C25B
ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR  [2]
 C25B

Note(s)

  1. In this sub-class, in the absence of an indication to the contrary an invention is classified in the last appropriate place. [2]
  2. Compounds are secondarily classified in the appropriate classes, e.g. C01, C07, if of interest. [2]

 C25C
PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR  [2]

 C25D
PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING (printed circuits by metal deposition H05K 3/18); APPARATUS THEREFOR  [2]

 C25F
PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS  [2]
 C25F

Note(s)

In this sub-class, an invention is classified in the last appropriate place. [2]