|  | 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 Section C covers: pure chemistry, which covers inorganic compounds, organic compounds, macromolecular compounds, and their methods of preparation; 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; 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; 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; metallurgy, ferrous or non-ferrous alloys. 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. 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 Fulltext... Hierarchy... Expanded...C03 and not by class Fulltext... Hierarchy... Expanded...F27. There are, however, some exceptions in which the mechanical (or non-chemical) aspect carries with it the chemical aspect, for example: Certain extractive processes, in subclass Fulltext... Hierarchy... Expanded...A61K; The chemical purification of air, in subclass Fulltext... Hierarchy... Expanded...A61L; Chemical methods of fire-fighting, in subclass Fulltext... Hierarchy... Expanded...A62D; Chemical processes and apparatus, in class Fulltext... Hierarchy... Expanded...B01; Impregnation of wood, in subclass Fulltext... Hierarchy... Expanded...B27K; Chemical methods of analysis or testing, in subclass Fulltext... Hierarchy... Expanded...G01N; Photographic materials and processes, in class Fulltext... Hierarchy... Expanded...G03, and, generally, the chemical treatment of textiles and the production of cellulose or paper, in section D. 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: treatment of plants or animals, covered by subclass Fulltext... Hierarchy... Expanded...A01N; foodstuffs, covered by class Fulltext... Hierarchy... Expanded...A23; ammunition or explosives, covered by class Fulltext... Hierarchy... Expanded...F42. 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 Fulltext... Hierarchy... Expanded...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.

CHEMISTRY

|  | C01 |
INORGANIC CHEMISTRY (processing powders of inorganic compounds preparatory to the manufacturing of ceramic products Fulltext... Hierarchy... Expanded...C04B 35/00; fermentation or enzyme-using processes for the preparation of elements or inorganic compounds except carbon dioxide Fulltext... Hierarchy... Expanded...C12P 3/00; obtaining metal compounds from mixtures, e.g. ores, which are intermediate compounds in a metallurgical process for obtaining a free metal Fulltext... Hierarchy... Expanded...C21B, Fulltext... Hierarchy... Expanded...C22B; production of non-metallic elements or inorganic compounds by electrolysis or electrophoresis Fulltext... Hierarchy... Expanded...C25B)

|  | C01 |
Note(s) In subclasses Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C01B-C01G, and within each of these subclasses, in the absence of an indication to the contrary, a compound is classified in the last appropriate place, e.g. potassium permanganate is classified only as a permanganate compound, in subclass Fulltext... Hierarchy... Expanded...C01G. [3] Biocidal, pest repellant, pest attractant or plant growth regulatory activity of compounds or preparations is further classified in subclass Fulltext... Hierarchy... Expanded...A01P. [8] Processes using enzymes or micro-organisms in order to: [5] liberate, separate or purify a pre-existing compound or composition, or to treat textiles or clean solid surfaces of materials are further classified in subclass Fulltext... Hierarchy... Expanded...C12S. [5]

|  | C01F |
COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS (metal hydrides Fulltext... Hierarchy... Expanded...C01B 6/00; salts of oxyacids of halogens Fulltext... Hierarchy... Expanded...C01B 11/00; peroxides, salts of peroxyacids Fulltext... Hierarchy... Expanded...C01B 15/00; sulfides or polysulfides of magnesium, calcium, strontium, or barium Fulltext... Hierarchy... Expanded...C01B 17/42; thiosulfates, dithionites, polythionates Fulltext... Hierarchy... Expanded...C01B 17/64; compounds containing selenium or tellurium Fulltext... Hierarchy... Expanded...C01B 19/00; binary compounds of nitrogen with metals Fulltext... Hierarchy... Expanded...C01B 21/06; azides Fulltext... Hierarchy... Expanded...C01B 21/08; metal amides Fulltext... Hierarchy... Expanded...C01B 21/092; nitrites Fulltext... Hierarchy... Expanded...C01B 21/50; phosphides Fulltext... Hierarchy... Expanded...C01B 25/08; salts of oxyacids of phosphorus Fulltext... Hierarchy... Expanded...C01B 25/16; carbides Fulltext... Hierarchy... Expanded...C01B 31/30; compounds containing silicon Fulltext... Hierarchy... Expanded...C01B 33/00; compounds containing boron Fulltext... Hierarchy... Expanded...C01B 35/00; compounds having molecular sieve properties but not having base-exchange properties Fulltext... Hierarchy... Expanded...C01B 37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, Fulltext... Hierarchy... Expanded...C01B 39/00; cyanides Fulltext... Hierarchy... Expanded...C01C 3/08; salts of cyanic acid Fulltext... Hierarchy... Expanded...C01C 3/14; salts of cyanamide Fulltext... Hierarchy... Expanded...C01C 3/16; thiocyanates Fulltext... Hierarchy... Expanded...C01C 3/20)

|  | C01F |
Note(s) Attention is drawn to Note (1) after class Fulltext... Hierarchy... Expanded...C01, which defines the last place priority rule applied in this class, i.e. in the range of subclasses Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C01B-C01G and within these subclasses. [8] Therapeutic activity of compounds is further classified in subclass Fulltext... Hierarchy... Expanded...A61P. [7]

P:70 |  | C01F 1/00 |
Methods of preparing compounds of the metals beryllium, magnesium, aluminium, calcium, strontium, barium, radium, thorium, or the rare earths, in general

P:60 |  | C01F 3/00 |
Compounds of beryllium

|  | C01F 3/02 |
· | Oxides; Hydroxides [3]

P:50 |  | C01F 5/00 |
Compounds of magnesium

|  | C01F 5/02 |
· | Magnesia

|  | C01F 5/04 |
· · | by oxidation of metallic magnesium

|  | C01F 5/06 |
· · | by thermal decomposition of magnesium compounds (calcining magnesite or dolomite Fulltext... Hierarchy... Expanded...C04B 2/10)

|  | C01F 5/08 |
· · · | by calcining magnesium hydroxide

|  | C01F 5/10 |
· · · | by thermal decomposition of magnesium chloride with water vapour

|  | C01F 5/12 |
· · · | by thermal decomposition of magnesium sulfate, with or without reduction

|  | C01F 5/14 |
· | Magnesium hydroxide

|  | C01F 5/16 |
· · | by treating magnesia, e.g. calcined dolomite, with water or solutions of salts not containing magnesium

|  | C01F 5/20 |
· · | by precipitation from solutions of magnesium salts with ammonia

|  | C01F 5/22 |
· · | from magnesium compounds with alkali hydroxides or alkaline earth oxides or hydroxides

|  | C01F 5/24 |
· | Magnesium carbonates

|  | C01F 5/26 |
· | Magnesium halides

|  | C01F 5/28 |
· · | Fluorides

|  | C01F 5/30 |
· · | Chlorides

|  | C01F 5/32 |
· · · | Preparation of anhydrous magnesium chloride by chlorinating magnesium compounds

|  | C01F 5/34 |
· · · | Dehydrating magnesium chloride containing water of crystallisation

|  | C01F 5/36 |
· · | Bromides

|  | C01F 5/38 |
· | Magnesium nitrates

|  | C01F 5/40 |
· | Magnesium sulfates (double sulfates of magnesium with sodium or potassium Fulltext... Hierarchy... Expanded...C01D 5/12, with other alkali metals Fulltext... Hierarchy... Expanded...C01D 15/06, Fulltext... Hierarchy... Expanded...C01D 17/00) [3]

|  | C01F 5/42 |
· | Magnesium sulfites

P:30 |  | C01F 7/00 |
Compounds of aluminium

|  | C01F 7/02 |
· | Aluminium oxide; Aluminium hydroxide; Aluminates

|  | C01F 7/04 |
· · | Preparation of alkali metal aluminates; Aluminium oxide or hydroxide therefrom

|  | C01F 7/06 |
· · · | by treating aluminous minerals with alkali hydroxide

|  | C01F 7/08 |
· · · | by treating aluminous minerals with sodium carbonate

|  | C01F 7/10 |
· · · | by treating aluminous minerals with alkali sulfates and reducing agents

|  | C01F 7/12 |
· · · | Alkali metal aluminates from alkaline earth metal aluminates

|  | C01F 7/14 |
· · · | Aluminium oxide or hydroxide from alkali metal aluminates

|  | C01F 7/16 |
· · | Preparation of alkaline earth metal aluminates; Aluminium oxide or hydroxide therefrom

|  | C01F 7/18 |
· · · | Aluminium oxide or hydroxide from alkaline earth metal aluminates

|  | C01F 7/20 |
· · | Preparation of aluminium oxide or hydroxide from aluminous ores with acids or salts

|  | C01F 7/22 |
· · · | with halides

|  | C01F 7/24 |
· · · | with nitric acid or nitrogen oxides

|  | C01F 7/26 |
· · · | with sulfuric acids or sulfates

|  | C01F 7/28 |
· · · | with sulfurous acid

|  | C01F 7/30 |
· · | Preparation of aluminium oxide or hydroxide by thermal decomposition of aluminium compounds

|  | C01F 7/32 |
· · · | of sulfates

|  | C01F 7/34 |
· · | Preparation of aluminium hydroxide by precipitation from solutions containing aluminium salts

|  | C01F 7/36 |
· · · | from organic aluminium salts

|  | C01F 7/38 |
· · | Preparation of aluminium oxide by thermal reduction of aluminous minerals

|  | C01F 7/40 |
· · · | in the presence of aluminium sulfide

|  | C01F 7/42 |
· · | Preparation of aluminium oxide or hydroxide from metallic aluminium, e.g. by oxidation

|  | C01F 7/44 |
· · | Dehydration of aluminium hydroxide

|  | C01F 7/46 |
· · | Purification of aluminium oxide, aluminium hydroxide or aluminates [5]

|  | C01F 7/47 |
· · · | of aluminates [5]

|  | C01F 7/48 |
· | Aluminium halides

|  | C01F 7/50 |
· · | Fluorides

|  | C01F 7/52 |
· · · | Double compounds containing both fluorine and other acid groups

|  | C01F 7/54 |
· · · | Double compounds containing both aluminium and alkali metals or alkaline earth metals

|  | C01F 7/56 |
· · | Chlorides (containing fluorine Fulltext... Hierarchy... Expanded...C01F 7/52) [3]

|  | C01F 7/58 |
· · · | Preparation of anhydrous aluminium chloride

|  | C01F 7/60 |
· · · · | from oxygen-containing aluminium compounds

|  | C01F 7/62 |
· · · | Purification

|  | C01F 7/64 |
· · | Bromides (containing fluorine Fulltext... Hierarchy... Expanded...C01F 7/52) [3]

|  | C01F 7/66 |
· | Aluminium nitrates (containing fluorine Fulltext... Hierarchy... Expanded...C01F 7/52) [3]

|  | C01F 7/68 |
· | Aluminium compounds containing sulfur (containing fluorine Fulltext... Hierarchy... Expanded...C01F 7/52) [3]

|  | C01F 7/70 |
· · | Sulfides

|  | C01F 7/72 |
· · | Sulfites

|  | C01F 7/74 |
· · | Sulfates

|  | C01F 7/76 |
· · · | Double salts, e.g. alums

P:40 |  | C01F 11/00 |
Compounds of calcium, strontium, or barium (Fulltext... Hierarchy... Expanded...C01F 7/00 takes precedence) [3]

|  | C01F 11/02 |
· | Oxides or hydroxides (production of lime Fulltext... Hierarchy... Expanded...C04B 2/00)

|  | C01F 11/04 |
· · | by thermal decomposition

|  | C01F 11/06 |
· · · | of carbonates

|  | C01F 11/08 |
· · | by reduction of sulfates

|  | C01F 11/10 |
· · | from sulfides

|  | C01F 11/12 |
· · | from silicates

|  | C01F 11/16 |
· · | Purification

|  | C01F 11/18 |
· | Carbonates

|  | C01F 11/20 |
· | Halides

|  | C01F 11/22 |
· · | Fluorides

|  | C01F 11/24 |
· · | Chlorides

|  | C01F 11/26 |
· · · | from sulfides

|  | C01F 11/28 |
· · · | by chlorination of alkaline earth metal compounds

|  | C01F 11/30 |
· · · | Concentrating; Dehydrating; Preventing the absorption of moisture or caking

|  | C01F 11/32 |
· · · | Purification

|  | C01F 11/34 |
· · | Bromides

|  | C01F 11/36 |
· | Nitrates

|  | C01F 11/38 |
· · | Preparation with nitric acid or nitrogen oxides

|  | C01F 11/40 |
· · | Preparation by double decomposition with nitrates

|  | C01F 11/42 |
· · | Double salts (with magnesium Fulltext... Hierarchy... Expanded...C01F 5/38)

|  | C01F 11/44 |
· · | Concentrating; Crystallising; Dehydrating; Preventing the absorption of moisture or caking

|  | C01F 11/46 |
· | Sulfates (dehydration of gypsum Fulltext... Hierarchy... Expanded...C04B 11/02)

|  | C01F 11/48 |
· | Sulfites

P:20 |  | C01F 13/00 |
Compounds of radium

P:10 |  | C01F 15/00 |
Compounds of thorium

P:0 |  | C01F 17/00 |
Compounds of the rare-earth metals, i.e. scandium, yttrium, lanthanum, or the group of the lanthanides