C
SECTION C — CHEMISTRY; METALLURGY
 C

Note(s)

In section C, the definitions of groups of chemical elements are as follows:

  • 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; working of metal by the action of a high concentration of electric current B23H; surface treatment of metallic material or coating involving at least one process provided for in class C23 and at least one process covered by this class C23C 28/00, C23F 17/00; anodic or cathodic protection C23F; single-crystal growth 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)  [4]
 C25

Note(s)

  1. Inventions dealing with electrolytic or electrophoretic processes or apparatus or operational features are classified
    1. in the groups for the compounds or articles produced, and [2]
    2. in the groups which cover the apparatus or operational features. [2]
  2. The electrolytic or electrophoretic purification of materials is classified according to the nature of the liquid in the relevant places, e.g. A01K 63/00, C02F 1/46, C25B 15/08, C25D 21/16, C25F 7/02[2]
 C25F
PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROM OBJECTS; APPARATUS THEREFOR  [2]
 C25F

Note(s)

In this subclass, in the absence of an indication to the contrary, an invention is classified in the last appropriate place. [2]

 C25F 1/00
Electrolytic cleaning, degreasing, pickling, or descaling  [2]
 C25F 1/02
·  Pickling; Descaling  [2]
 C25F 1/04
·  ·  in solution  [2]
 C25F 1/06
·  ·  ·  of iron or steel  [2]
 C25F 1/08
·  ·  ·  of refractory metals  [2]
 C25F 1/10
·  ·  ·  of actinides  [2]
 C25F 1/12
·  ·  in melts  [2]
 C25F 1/14
·  ·  ·  of iron or steel  [2]
 C25F 1/16
·  ·  ·  of refractory metals  [2]
 C25F 1/18
·  ·  ·  of actinides  [2]
 C25F 3/00
Electrolytic etching or polishing  [2]
 C25F 3/02
·  Etching  [2]
 C25F 3/04
·  ·  of light metals  [2]
 C25F 3/06
·  ·  of iron or steel  [2]
 C25F 3/08
·  ·  of refractory metals  [2]
 C25F 3/10
·  ·  of actinides  [2]
 C25F 3/12
·  ·  of semiconducting materials  [2]
 C25F 3/14
·  ·  locally  [2]
 C25F 3/16
·  Polishing  [2]
 C25F 3/18
·  ·  of light metals  [2]
 C25F 3/20
·  ·  ·  of aluminium  [2]
 C25F 3/22
·  ·  of heavy metals  [2]
 C25F 3/24
·  ·  ·  of iron or steel  [2]
 C25F 3/26
·  ·  ·  of refractory metals  [2]
 C25F 3/28
·  ·  ·  of actinides  [2]
 C25F 3/30
·  ·  of semiconducting materials  [2]
 C25F 5/00
Electrolytic stripping of metallic layers or coatings  [2]
 C25F 7/00
Constructional parts, or assemblies thereof, of cells for electrolytic removal of material from objects (for both electrolytic coating and removal C25D); Servicing or operating  [2]
 C25F 7/02
·  Regeneration of process liquids  [2]