|  | 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 The following notes are meant to assist in the use of this part of the classification scheme. They must not be read as modifying in any way the elaborations. 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 this class, in the absence of an indication to the contrary, a compound is classified in the last appropriate place. [3] Processes using enzymes or micro-organisms in order to: 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]

|  | C02 |
TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE (settling tanks, filtering, e.g. sand filters or screening devices, Fulltext... Hierarchy... Expanded...B01D)

|  | C03 |
GLASS; MINERAL OR SLAG WOOL

|  | C04 |
CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES (alloys based on refractory metals Fulltext... Hierarchy... Expanded...C22C) [4]

|  | C04 |
Note(s) This class does not cover mechanical features provided for elsewhere, e.g. mechanical working Fulltext... Hierarchy... Expanded...B28, kilns Fulltext... Hierarchy... Expanded...F27.

|  | C05 |
FERTILISERS; MANUFACTURE THEREOF (processes or devices for granulating materials, in general Fulltext... Hierarchy... Expanded...B01J 2/00; soil-conditioning or soil-stabilising materials Fulltext... Hierarchy... Expanded...C09K 17/00) [4]

|  | C05 |
Note(s) An ingredient in a mixture of fertilisers, or a single fertiliser which contains more than one of the chemical elements on which the subdivision into subclasses is based, is classified only in the first of the appropriate subclasses. Thus, a nitrophosphate or an ammoniated superphosphate is classified in Fulltext... Hierarchy... Expanded...C05B but not in Fulltext... Hierarchy... Expanded...C05C, magnesium phosphate is classified in Fulltext... Hierarchy... Expanded...C05B but not in Fulltext... Hierarchy... Expanded...C05D, and calcium cyanamide in Fulltext... Hierarchy... Expanded...C05C but not in Fulltext... Hierarchy... Expanded...C05D. In this class, it is desirable to add the indexing codes relating to ingredients of a mixture of different fertilisers or of fertilisers with non-fertilisers. The indexing codes, which are chosen from the groups in this class, with the exception of groups Fulltext... Hierarchy... Expanded...C05B 1/10 and Fulltext... Hierarchy... Expanded...C05B 11/02, Fulltext... Hierarchy... Expanded...C05C 1/02 and Fulltext... Hierarchy... Expanded...C05C 7/02, Fulltext... Hierarchy... Expanded...C05F 1/02, Fulltext... Hierarchy... Expanded...C05F 3/06, Fulltext... Hierarchy... Expanded...C05F 9/02, Fulltext... Hierarchy... Expanded...C05F 11/06 and Fulltext... Hierarchy... Expanded...C05F 17/02, have the same numbers as the classification symbols, but a colon is used instead of the oblique stroke, and should be linked.

|  | C06 |
EXPLOSIVES; MATCHES

|  | C07 |
ORGANIC CHEMISTRY (such compounds as the oxides, sulfides, or oxysulfides of carbon, cyanogen, phosgene, hydrocyanic acid or salts thereof Fulltext... Hierarchy... Expanded...C01; products obtained from layered base-exchange silicates by ion-exchange with organic compounds such as ammonium, phosphonium or sulfonium compounds or by intercalation of organic compounds Fulltext... Hierarchy... Expanded...C01B 33/44; macromolecular compounds Fulltext... Hierarchy... Expanded...C08; dyes Fulltext... Hierarchy... Expanded...C09; fermentation products Fulltext... Hierarchy... Expanded...C12; fermentation or enzyme-using processes to synthesise a desired chemical compound or composition or to separate optical isomers from a racemic mixture Fulltext... Hierarchy... Expanded...C12P; production of organic compounds by electrolysis or electrophoresis Fulltext... Hierarchy... Expanded...C25B 3/00, Fulltext... Hierarchy... Expanded...C25B 7/00) [2]

|  | C07 |
Note(s) In this class, the following term is used with the meaning indicated: "preparation" covers purification, separation, stabilisation or use of additives, unless a separate place is provided therefor. [4] In this class, in the absence of an indication to the contrary, and with the exception referred to below, a compound is classified in the last appropriate place, e.g. a compound containing an acyclic chain and a heterocyclic ring is classified only as a heterocyclic compound, and a steroid is classified only as a cyclopentanophenanthrene compound. In general, and in the absence of an indication to the contrary (such as groups Fulltext... Hierarchy... Expanded...C07C 59/58, Fulltext... Hierarchy... Expanded...C07C 59/70), the terms "acyclic" and "aliphatic" are used to describe compounds in which there is no ring; and, if a ring were present, the compound would be taken by the "last place" rule to a later group for cycloaliphatic or aromatic compounds, if such a group exists. Where a compound or an entire group of compounds exists in tautomeric forms, it is classified as though existing in the form which is classified last in the system, unless the other form is specifically mentioned earlier in the system. Chemical compounds and their preparation are classified in the groups for the type of compound prepared. The processes of preparation are also classified in the groups for the types of reaction employed, if of interest. General processes for the preparation of a class of compounds falling into more than one main group are classified in the groups for the processes employed, when such groups exist. The compounds prepared are also classified in the groups for the types of compound prepared, if of interest. In this class, in the absence of an indication to the contrary, the compounds containing carboxyl or thiocarboxyl groups are classified as the relevant carboxylic or thiocarboxylic acids, unless the "last place rule" (see Note (2), above) dictates otherwise; a carboxyl group being a carbon atom having three bonds, and no more than three, to hetero atoms, other than nitrogen atoms of nitro or nitroso groups, with at least one multiple bond to the same hetero atom and a thiocarboxyl group being a carboxyl group having at least one bond to a sulfur atom, e.g. amides or nitriles of carboxylic acids, are classified with the corresponding acids. [5] Salts of a compound, unless specifically provided for, are classified as that compound, e.g. aniline hydrochloride is classified as containing carbon, hydrogen and nitrogen only (in group Fulltext... Hierarchy... Expanded...C07C 211/46), sodium malonate is classified as malonic acid (in Fulltext... Hierarchy... Expanded...C07C 55/08), and a mercaptide is classified as the mercaptan. Metal chelates are dealt with in the same way. Similarly, metal alcoholates and metal phenates are classified in subclass Fulltext... Hierarchy... Expanded...C07C and not in subclass Fulltext... Hierarchy... Expanded...C07F, the alcoholates in groups Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C07C 31/28-C07C 31/32 and the phenates as the corresponding phenols in group Fulltext... Hierarchy... Expanded...C07C 39/235 or Fulltext... Hierarchy... Expanded...C07C 39/44. Salts, adducts or complexes formed between two or more organic compounds are classified according to all compounds forming the salts, adducts or complexes [2] The codes of subclass Fulltext... Hierarchy... Expanded...C07M are only for use as indexing codes associated with subclasses Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C07B-C07K, so as to provide information concerning specific properties of organic compounds. [6]

|  | C08 |
ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON (manufacture or treatment of artificial threads, fibres, bristles or ribbons Fulltext... Hierarchy... Expanded...D01)

|  | C08 |
Note(s) Processes using enzymes or micro-organisms in order to: 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]

|  | C09 |
DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; MISCELLANEOUS COMPOSITIONS; MISCELLANEOUS APPLICATIONS OF MATERIALS

|  | C10 |
PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT

|  | C11 |
ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES (edible oil or fat compositions Fulltext... Hierarchy... Expanded...A23)

|  | C12 |
BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING

|  | C12 |
Note(s) In subclasses Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C12M-C12Q or Fulltext... Hierarchy... Expanded...C12S, and within each of these subclasses, in the absence of an indication to the contrary, classification is made in the last appropriate place. [3] In this class, viruses, undifferentiated human, animal or plant cells, protozoa, tissues and unicellular algae are considered as micro-organisms. [3,5] In this subclass, unless specifically provided for, undifferentiated human, animal or plant cells, protozoa, tissues and unicellular algae are classified together with micro-organisms. Sub-cellular parts, unless specifically provided for, are classified with the whole cell. [5] The codes of subclass Fulltext... Hierarchy... Expanded...C12R are only for use as indexing codes associated with subclasses Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...C12C-C12Q or Fulltext... Hierarchy... Expanded...C12S, so as to provide information concerning the micro-organisms used in the processes classified in these subclasses. [3]

|  | C13 |
SUGAR INDUSTRY (polysaccharides, e.g. starch, derivatives thereof Fulltext... Hierarchy... Expanded...C08B; malt Fulltext... Hierarchy... Expanded...C12C) [4]

|  | C13 |
Note(s) Processes using enzymes or micro-organisms in order to: 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]

|  | C14 |
SKINS; HIDES; PELTS; LEATHER

METALLURGY

|  | C21 |
METALLURGY OF IRON

|  | C22 |
METALLURGY (of iron Fulltext... Hierarchy... Expanded...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 Fulltext... Hierarchy... Expanded...C21D; production of metals by electrolysis or electrophoresis Fulltext... Hierarchy... Expanded...C25)

|  | C22 |
Note(s) The codes of subclass Fulltext... Hierarchy... Expanded...C22K are only for use as indexing codes associated with subclasses Fulltext... Hierarchy... Expanded...C21D, Fulltext... Hierarchy... Expanded...C22C or Fulltext... Hierarchy... Expanded...C22F, so as to provide information concerning changing the physical characteristics of alloys. [6]

|  | C23 |
COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL (by metallising textiles Fulltext... Hierarchy... Expanded...D06M 11/83; decorating textiles by locally metallising Fulltext... Hierarchy... Expanded...D06Q 1/04); CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (for specific applications, see the relevant places, e.g. for manufacturing resistors Fulltext... Hierarchy... Expanded...H01C 17/06); INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL (treating metal surfaces or coating of metals by electrolysis or electrophoresis Fulltext... Hierarchy... Expanded...C25D, Fulltext... Hierarchy... Expanded...C25F) [2]

|  | C23 |
Note(s) In this class, the following expression is used with the meaning incicated: "metallic material" covers: metals; [4] alloys (attention is drawn to the Note following the title of subclass Fulltext... Hierarchy... Expanded...C22C).

|  | C25 |
ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR (electrodialysis, electro-osmosis, separation of liquids by electricity Fulltext... Hierarchy... Expanded...B01D; working of metal by the action of a high concentration of electric current Fulltext... Hierarchy... Expanded...B23H; treatment of water, waste water or sewage by electrochemical methods Fulltext... Hierarchy... Expanded...C02F 1/46; surface treatment of metallic material or coating involving at least one process provided for in class Fulltext... Hierarchy... Expanded...C23 and at least one process covered by this class Fulltext... Hierarchy... Expanded...C23C 28/00, Fulltext... Hierarchy... Expanded...C23F 17/00; anodic or cathodic protection Fulltext... Hierarchy... Expanded...C23F; single-crystal growth Fulltext... Hierarchy... Expanded...C30B; metallising textiles Fulltext... Hierarchy... Expanded...D06M 11/83; decorating textiles by locally metallising Fulltext... Hierarchy... Expanded...D06Q 1/04; electrochemical methods of analysis Fulltext... Hierarchy... Expanded...G01N; electrochemical measuring, indicating or recording devices Fulltext... Hierarchy... Expanded...G01R; electrolytic circuit elements, e.g. capacitors, Fulltext... Hierarchy... Expanded...H01G; electrochemical current or voltage generators Fulltext... Hierarchy... Expanded...H01M) [4]

|  | C25 |
Note(s) Electrolytic or electrophoretic processes or apparatus or operational features are classified in the groups for the compounds or articles produced, and in the groups which cover the apparatus or operational features. [2] The electrolytic or electrophoretic purification of materials is classified according to the nature of the liquid in the relevant places, e.g. Fulltext... Hierarchy... Expanded...A01K 63/00, Fulltext... Hierarchy... Expanded...C02F 1/46, Fulltext... Hierarchy... Expanded...C25B 15/08, Fulltext... Hierarchy... Expanded...C25D 21/16, Fulltext... Hierarchy... Expanded...C25F 7/02. [2]

|  | C25 |
Class index
ELECTROLYTIC PRODUCTION |
Inorganic compounds, non-metals | C25B 1/00
Organic compounds | C25B 3/00
Non-metallic coatings | C25D 9/00
Metals | C25C 1/00, C25C 3/00, C25C 5/00
Metallic coatings | C25D 3/00, C25D 5/00, C25D 7/00
ELECTROLYTIC PRODUCTION OF COMPOUNDS OR NON-METALS WITH SIMULTANEOUS PRODUCTION OF ELECTRICITY | C25B 5/00
ELECTROPHORETIC PRODUCTION |
Compounds, non-metals | C25B 7/00
Coatings | C25D 13/00
ELECTROFORMING | C25D 1/00
ANODISING, PHOSPHATISING, CHROMATISING | C25D 11/00
COATINGS WITH EMBEDDED MATERIAL | C25D 15/00
ELECTROLYTIC CLEANING, PICKLING, OR REMOVAL OF METALLIC COATINGS | C25F 1/00, C25F 5/00
ELECTROLYTIC ETCHING OR POLISHING | C25F 3/00
CELLS, ELECTRODES, DIAPHRAGMS |
Production of compounds or non-metals | C25B 9/00, C25B 11/00, C25B 13/00, C25B 15/00
Production of metals | C25C 7/00
Production of coatings | C25D 17/00, C25D 19/00, C25D 21/00
Cleaning, pickling, surface treatment | C25F 7/00

|  | C30 |
CRYSTAL GROWTH (separation by crystallisation in general Fulltext... Hierarchy... Expanded...B01D 9/00) [3]