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]
 C25B
ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR  [2]
 C25B

Note(s)

  1. In this subclass, in the absence of an indication to the contrary, an invention is classified in the last appropriate place. [2]
  2. Compounds of particular interest are also classified in the relevant classes, e.g. in C01, C07[2]
 C25B 1/00
Electrolytic production of inorganic compounds or non-metals  [2]
 C25B 1/02
·  of hydrogen or oxygen  [2]
 C25B 1/04
·  ·  by electrolysis of water  [2]
 C25B 1/06
·  ·  ·  in cells with flat or platelike electrodes  [2]
 C25B 1/08
·  ·  ·  ·  of the filter-press type  [2]
 C25B 1/10
·  ·  ·  in diaphragm cells  [2]
 C25B 1/12
·  ·  ·  in pressure cells  [2]
 C25B 1/14
·  of alkali metal compounds  [2]
 C25B 1/16
·  ·  Hydroxides  [2]
 C25B 1/18
·  of alkaline earth metal compounds or magnesium compounds  [2]
 C25B 1/20
·  ·  Hydroxides  [2]
 C25B 1/22
·  of inorganic acids  [2]
 C25B 1/24
·  of halogens or compounds thereof  [2]
 C25B 1/26
·  ·  Chlorine; Compounds thereof  [2]
 C25B 1/28
·  of per-compounds  [2]
 C25B 1/30
·  ·  Peroxides  [2]
 C25B 1/32
·  ·  Perborates  [2]
 C25B 1/34
·  Simultaneous production of alkali metal hydroxides and chlorine, its oxyacids or salts  [2]
 C25B 1/36
·  ·  in mercury cathode cells  [2]
 C25B 1/38
·  ·  ·  with vertical mercury cathode  [2]
 C25B 1/40
·  ·  ·  with horizontal mercury cathode  [2]
 C25B 1/42
·  ·  ·  Decomposition of amalgams  [2]
 C25B 1/44
·  ·  ·  ·  with the aid of catalysts  [2]
 C25B 1/46
·  ·  in diaphragm cells  [2]
 C25B 3/00
Electrolytic production of organic compounds  [2]
 C25B 3/02
·  by oxidation  [2]
 C25B 3/04
·  by reduction  [2]
 C25B 3/06
·  by halogenation  [2]
 C25B 3/08
·  ·  by fluorination  [2]
 C25B 3/10
·  by coupling reactions, e.g. dimerisation  [2]
 C25B 3/12
·  of organometallic compounds  [2]
 C25B 5/00
Electrogenerative processes, i.e. processes for producing compounds in which simultaneously electricity is generated  [2]
 C25B 7/00
Electrophoretic production of compounds or non-metals (separation or purification of proteins by electrophoresis C07K 3/14)  [2]
 C25B 9/00
Constructional parts, or assemblies thereof, of cells (C25B 11/00, C25B 13/00 take precedence)  [2]
 C25B 9/02
·  Holders for electrodes  [2]
 C25B 9/04
·  Devices for current supply (electrical connections per se H01R); Electrode connections; Electric inter-cell connections  [2]
 C25B 11/00
Electrodes; Manufacture thereof not otherwise provided for  [2]
 C25B 11/02
·  characterised by shape or form  [2]
 C25B 11/03
·  ·  perforated or foraminous  [2]
 C25B 11/04
·  characterised by the material  [2]
 C25B 11/06
·  ·  by the catalytic materials used (catalysts in general B01J)  [2]
 C25B 11/08
·  ·  ·  Noble metals  [2]
 C25B 11/10
·  ·  Electrodes based on barrier-type metals, e.g. titanium  [2]
 C25B 11/12
·  ·  Electrodes based on carbon (carbon masses in general C04B 35/52)  [2]
 C25B 11/14
·  ·  ·  Impregnation of carbon electrodes (C25B 11/06 takes precedence)  [2]
 C25B 11/16
·  ·  Electrodes based on manganese dioxide or lead dioxide  [2]
 C25B 11/18
·  ·  Mercury or amalgam electrodes  [2]
 C25B 11/20
·  Electrode-membrane assemblies characterised by having electrode catalyst embedded in, or on, the surface of ion-exchange membranes  [4]
 C25B 13/00
Diaphragms; Spacing elements (C25B 11/20 takes precedence)  [2]
 C25B 13/02
·  characterised by form or shape  [2]
 C25B 13/04
·  characterised by the material  [2]
 C25B 13/06
·  ·  based on asbestos  [2]
 C25B 13/08
·  ·  based on organic materials  [2]
 C25B 15/00
Operating or servicing of cells  [2]
 C25B 15/02
·  Process control or regulation (controlling or regulating in general G05)  [2]
 C25B 15/04
·  Regulation of the inter-electrode distance (working of metal by the action of a high concentration of electric current B23H)  [2]
 C25B 15/06
·  Detection or inhibition of short circuits in the cell  [2]
 C25B 15/08
·  Supplying or removing reactants or electrolytes; Regeneration of electrolytes  [2]