|  | 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

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

|  | C10H |
PRODUCTION OF ACETYLENE BY WET METHODS (purification of acetylene Fulltext... Hierarchy... Expanded...C07C 11/24) [5]

|  | C10H |
Subclass index
GENERATORS |
With non-automatic water feed | 1/00
With automatic water feed | 3/00, 5/00
Kipp's or Dobereiner's type | 7/00, 9/00
Other types | 11/00 - 19/00
Details | 21/00

P:50 |  | C10H 1/00 |
Acetylene gas generators with dropwise, gravity, non-automatic water feed (valves, cocks Fulltext... Hierarchy... Expanded...F16K)

|  | C10H 1/02 |
· | Valves

|  | C10H 1/04 |
· · | Screw valves

|  | C10H 1/06 |
· · | Cocks

|  | C10H 1/08 |
· | Other means for controlling the water feed

|  | C10H 1/10 |
· | Water feed from above through a central or lateral pipe

|  | C10H 1/12 |
· | Water feed from above through porous materials

P:40 |  | C10H 3/00 |
Acetylene gas generators with automatic water feed regulation by means independent of the gas-holder

|  | C10H 3/02 |
· | with membranes

|  | C10H 3/04 |
· | with floats

|  | C10H 3/06 |
· | with pistons

P:30 |  | C10H 5/00 |
Acetylene gas generators with automatic water feed regulation by the gas-holder

|  | C10H 5/02 |
· | with overflow for the water

|  | C10H 5/04 |
· | by drop-by-drop water valves connected with the gas-holder

|  | C10H 5/06 |
· · | by drop-by-drop water cocks connected with the gas-holder

|  | C10H 5/08 |
· | with gas-holder-connected water valves or cocks according to the submersion system

P:20 |  | C10H 7/00 |
Acetylene gas generators with water feed by Kipp's principle

|  | C10H 7/02 |
· | with water feed from below

|  | C10H 7/04 |
· | with water feed from above

P:10 |  | C10H 9/00 |
Acetylene gas generators according to Dobereiner's principle with fixed carbide bell

|  | C10H 9/02 |
· | with water feed from below through porous materials (by capillary feed)

|  | C10H 9/04 |
· | with gas cock actuated by the gas-holder

|  | C10H 9/06 |
· | with the depth of the gas outlet pipe regulated by the gas-holder

|  | C10H 9/08 |
· | with movable gas-holder

|  | C10H 9/10 |
· | by wetting the carbide only at the bottom

P:60 |  | C10H 11/00 |
Acetylene gas generators with submersion of the carbide in water

|  | C10H 11/02 |
· | inside the gas-holder

|  | C10H 11/04 |
· | with sealing and reaction water separated from each other

P:0 |  | C10H 13/00 |
Acetylene gas generators with combined dipping and drop-by-drop system

P:70 |  | C10H 15/00 |
Acetylene gas generators with carbide feed, with or without regulation by the gas pressure

|  | C10H 15/02 |
· | with non-automatic carbide feed

|  | C10H 15/04 |
· · | Closure means at the filling-hopper

|  | C10H 15/06 |
· | with automatic carbide feed by valves

|  | C10H 15/08 |
· · | by flap or slide valves

|  | C10H 15/10 |
· · | by float valves

|  | C10H 15/12 |
· · | by measuring valves, including pocket-wheels

|  | C10H 15/14 |
· | with feed worm or feed conveyers

|  | C10H 15/16 |
· | with feed drums

|  | C10H 15/18 |
· | with movable feed disc and fixed carbide-receptacle

|  | C10H 15/20 |
· | with carbide feed by cartridges or other packets

|  | C10H 15/22 |
· | with carbide feed of pulverous carbide from receptacles or through the gas-holder

|  | C10H 15/24 |
· | with carbide feed by pistons

P:80 |  | C10H 17/00 |
High-pressure acetylene gas generators

P:90 |  | C10H 19/00 |
Other acetylene gas generators

|  | C10H 19/02 |
· | Rotary carbide receptacles

P:100 |  | C10H 21/00 |
Details of acetylene generators; Accessory equipment for, or features of, the wet production of acetylene

|  | C10H 21/02 |
· | Packages of carbide for use in generators, e.g. cartridges

|  | C10H 21/04 |
· · | Placing packages in the generator

|  | C10H 21/06 |
· · · | Opening devices for packages in the generator

|  | C10H 21/08 |
· | Safety devices for acetylene generators

|  | C10H 21/10 |
· | Carbide compositions

|  | C10H 21/12 |
· | Gas-tight sealing means, e.g. liquid seals in generators

|  | C10H 21/14 |
· | Ventilation means; Cooling devices

|  | C10H 21/16 |
· | Removing sludge from generators