C
SECTION C — CHEMISTRY; METALLURGY
 C

Note(s)

  1. 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

  2. Section C covers :
    1. pure chemistry, which covers inorganic compounds, organic compounds, macromolecular compounds, and their methods of preparation;
    2. applied chemistry, which covers compositions containing the above compounds, such as: glass, ceramics, fertilisers, plastics compositions, paints, products of the petroleum industry. It also covers certain compositions on account of their having particular properties rendering them suitable for certain purposes, as in the case of explosives, dyestuffs, adhesives, lubricants, and detergents;
    3. certain marginal industries, such as the manufacture of coke and of solid or gaseous fuels, the production and refining of oils, fats and waxes, the fermentation industry (e.g., brewing and wine-making), the sugar industry;
    4. certain operations or treatments, which are either purely mechanical, e.g., the mechanical treatment of leather and skins, or partly mechanical, e.g., the treatment of water or the prevention of corrosion in general;
    5. metallurgy, ferrous or non-ferrous alloys.
  3. In all sections of the IPC, in the absence of an indication to the contrary, the Periodic System of chemical elements referred to is the one with 8 groups as represented in the table below. For example, group C07F 3/00 "Compounds containing elements of the 2nd Group of the Periodic System" refers to the elements of columns IIa and IIb. [2009.01]

    1. In the case of operations, treatments, products or articles having both a chemical and a non-chemical part or aspect, the general rule is that the chemical part or aspect is covered by section C.
    2. In some of these cases, the chemical part or aspect brings with it a non-chemical one, even though purely mechanical, because this latter aspect either is essential to the operation or treatment or constitutes an important element thereof. It has seemed, in fact, more logical not to dissociate the different parts or aspects of a coherent whole. This is the case for applied chemistry and for the industries, operations and treatments mentioned in Notes (1)(c), (d) and (e). For example, furnaces peculiar to the manufacture of glass are covered by class C03 and not by class F27.
    3. There are, however, some exceptions in which the mechanical (or non-chemical) aspect carries with it the chemical aspect, for example:
    4. In still other cases, the pure chemical aspect is covered by section C and the applied chemical aspect by another section, such as A, B or F, e.g., the use of a substance or composition for:
    5. When the chemical and mechanical aspects are so closely interlocked that a neat and simple division is not possible, or when certain mechanical processes follow as a natural or logical continuation of a chemical treatment, section C may cover, in addition to the chemical aspect, a part only of the mechanical aspect, e.g., after-treatment of artificial stone, covered by class C04. In this latter case, a note or a reference is usually given to make the position clear, even if sometimes the division is rather arbitrary.
  
METALLURGY
 C22
METALLURGY (of iron C21); FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS (general methods or devices for heat treatment of ferrous or non-ferrous metals or alloys C21D; production of metals by electrolysis or electrophoresis C25)
 C22B
PRODUCTION OR REFINING OF METALS (making metallic powder or suspensions thereof B22F 9/00; electrolytic C25); PRETREATMENT OF RAW MATERIALS
 C22B

Note(s)

  1. In this subclass, groups for obtaining metals include obtaining the metals by non-metallurgical processes, and obtaining metal compounds by metallurgical processes. Thus, for example, group C22B 11/00 covers the production of silver by reduction of ammoniacal silver oxide in solution, and group C22B 17/00 covers the production of cadmium oxide by a metallurgical process. Furthermore, although compounds of arsenic and antimony are classified in C01G, production of the elements themselves is covered by C22B, as well as the production of their compounds by metallurgical processes.
  2. Processes using enzymes or micro-organisms in order to:
    1. liberate, separate or purify a pre-existing compound or composition, or to
    2. treat textiles or clean solid surfaces of materials
    are further classified in subclass C12S.  [5]
 C22B
Subclass index
PRETREATMENT OF RAW MATERIALS 1/00, 4/00, 7/00
PROCESSES FOR OBTAINING METALS 3/00, 4/00, 5/00
REFINING OR REMELTING METALS 9/00
OBTAINING SPECIFIC METALS 11/00 - 61/00
P:220 C22B 1/00
Preliminary treatment of ores or scrap
 C22B 1/14
·  Agglomerating; Briquetting; Binding; Granulating
 C22B 1/16
·  ·  Sintering; Agglomerating
P:210 C22B 3/00
Extraction of metal compounds from ores or concentrates by wet processes  [5]
 C22B 3/00

Note(s)

When classifying in this group, the nature of any metal which is considered to represent information of interest for search may also be classified in the main groups only of C22B 11/00-C22B 25/00, in group C22B 19/00 or in any of groups C22B 26/00-C22B 61/00. This can, for example, be the case when it is considered of interest to enable searching for extraction of specific metals or their compounds. Such non-obligatory classification should be given as "additional information". [8]

P:200 C22B 4/00
Electrothermal treatment of ores or metallurgical products for obtaining metals or alloys (general methods of refining or remelting metals C22B 9/00; obtaining iron or steel C21B, C21C)  [2]
P:230 C22B 5/00
General processes of reducing to metals
P:190 C22B 7/00
Working-up raw materials other than ores, e.g. scrap, to produce non-ferrous metals or compounds thereof
 C22B 7/02
·  Working-up flue dust
 C22B 7/04
·  Working-up slag
P:240 C22B 9/00
General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
 C22B 9/02
·  Refining by liquating, filtering, centrifuging, distilling or supersonic wave action
 C22B 9/16
·  Remelting metals (liquating C22B 9/02)  [3]
P:170 C22B 11/00
Obtaining noble metals
P:160 C22B 13/00
Obtaining lead
P:150 C22B 15/00
Obtaining copper
P:140 C22B 17/00
Obtaining cadmium
P:130 C22B 19/00
Obtaining zinc or zinc oxide (purifying zinc oxide C01G 9/00)
P:120 C22B 21/00
Obtaining aluminium
P:110 C22B 23/00
Obtaining nickel or cobalt
P:100 C22B 25/00
Obtaining tin
P:90 C22B 26/00
Obtaining alkali, alkaline earth metals or magnesium  [2]
P:80 C22B 30/00
Obtaining antimony, arsenic or bismuth  [2]
P:70 C22B 34/00
Obtaining refractory metals  [2]
P:60 C22B 35/00
Obtaining beryllium
P:50 C22B 41/00
Obtaining germanium
P:40 C22B 43/00
Obtaining mercury
P:30 C22B 47/00
Obtaining manganese
P:20 C22B 58/00
Obtaining gallium or indium  [2]
P:10 C22B 59/00
Obtaining rare earth metals
P:0 C22B 60/00
Obtaining metals of atomic number 87 or higher, i.e. radioactive metals  [2]
P:180 C22B 61/00
Obtaining metals not elsewhere provided for in this subclass (iron C21)  [2]