|  | 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 Fulltext... Hierarchy... Expanded...D06Q 1/04); INHIBITING CORROSION OR INCRUSTATION IN GENERAL (treating metal surfaces or coating of metals by electrolysis or electrophoresis Fulltext... Hierarchy... Expanded...C25D, Fulltext... Hierarchy... Expanded...C25F) [2]

|  | C23C |
APPARATUS AND PROCESSES FOR WHICH PROVISION IS NOT MADE ELSEWHERE, e.g. IN CLASSES Fulltext... Hierarchy... Expanded...B05, Fulltext... Hierarchy... Expanded...B44 OR IN SUB-CLASSES Fulltext... Hierarchy... Expanded...C03C, Fulltext... Hierarchy... Expanded...C23D, Fulltext... Hierarchy... Expanded...C23F, Fulltext... Hierarchy... Expanded...C25D, Fulltext... Hierarchy... Expanded...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 Fulltext... Hierarchy... Expanded...C03C)

|  | C23F |
CHEMICAL SURFACE TREATMENT OF METALS NOT COVERED BY SUB-CLASSES Fulltext... Hierarchy... Expanded...C23D, Fulltext... Hierarchy... Expanded...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: protective layers or coating compositions or methods of applying them; these are classified in the relevant class, e.g. Fulltext... Hierarchy... Expanded...B05, Fulltext... Hierarchy... Expanded...B44, Fulltext... Hierarchy... Expanded...C09D. mechanical devices or constructional features of particular articles; these are classified in the relevant class, e.g. pipes, pipe fittings Fulltext... Hierarchy... Expanded...F16L. 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 Fulltext... Hierarchy... Expanded...F01D 5/28.

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