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
 C23
WORKING OR TREATMENT OF METALS, OTHER THAN BY MECHANICAL MEANS; COVERING MATERIALS WITH METALS (decorating textiles by metallising D06Q 1/04); INHIBITING CORROSION OR INCRUSTATION IN GENERAL (treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D, C25F)  [2]
 C23C
APPARATUS AND PROCESSES FOR WHICH PROVISION IS NOT MADE ELSEWHERE, e.g. IN CLASSES B05, B44 OR IN SUB-CLASSES C03C, C23D, C23F, C25D, F27B, FOR COVERING METALS OR COVERING OTHER MATERIALS WITH METALS; DIFFUSION PROCESSES FOR SURFACE TREATMENT OF METALS

 C23D
ENAMELLING OF, AND APPLYING A VITREOUS LAYER TO, METALS (chemical composition of the enamels C03C)

 C23F
CHEMICAL SURFACE TREATMENT OF METALS NOT COVERED BY SUB-CLASSES C23D, C25D; INHIBITING CORROSION OR INCRUSTATION IN GENERAL
 C23F

Note(s)

This sub-class is the general place for inhibiting corrosion or incrustation in general, whether of or on metallic or non-metallic surfaces. It does not include, however:

  1. protective layers or coating compositions or methods of applying them; these are classified in the relevant class, e.g. B05, B44, C09D.
  2. mechanical devices or constructional features of particular articles; these are classified in the relevant class, e.g. pipes, pipe fittings F16L.
  3. articles characterised by being made of materials selected for their properties of resistance to corrosion or incrustation; these are classified in the relevant class, e.g. turbine blades F01D 5/28.


 C23G
CLEANING AND DE-GREASING OF METALLIC OBJECTS BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS (polishing compositions C09G; detergents in general C11D)