IPC Publication

C
CHEMISTRY; METALLURGY

Note(s) [2009.01]

  • 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 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 18 groups as represented in the table below.
    • fig401
    • 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 C03 and not by class 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 A61K;
      • The chemical purification of air, in subclass A61L;
      • Chemical methods of fire-fighting, in subclass A62D;
      • Chemical processes and apparatus, in class B01;
      • Impregnation of wood, in subclass B27K;
      • Chemical methods of analysis or testing, in subclass G01N;
      • Photographic materials and processes, in class 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 A01N;
      • foodstuffs, covered by class A23;
      • ammunition or explosives, covered by class 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 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

Note(s) [2006.01]

  • In subclasses C01B-C01G, the last place priority rule is applied, i.e. at each hierarchical level, 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 C01G.
  • Biocidal, pest repellant, pest attractant or plant growth regulatory activity of compounds or preparations is further classified in subclass A01P.
C01B
NON-METALLIC ELEMENTS; COMPOUNDS THEREOF (fermentation or enzyme-using processes for the preparation of elements or inorganic compounds except carbon dioxide C12P 3/00; production of non-metallic elements or inorganic compounds by electrolysis or electrophoresis C25B)

Note(s) [2006.01]

  • In this subclass, tradenames that are often found in scientific and patent literature have been used in order to define precisely the scope of the groups.
  • Attention is drawn to the definitions of groups of chemical elements following the title of section C.
  • Attention is drawn to Note (1) after class C01, which defines the last place priority rule applied in this class, i.e. in the range of subclasses C01B-C01G and within these subclasses.
  • Therapeutic activity of compounds is further classified in subclass A61P.
Hydrogen; Hydrides; Water; Synthesis gas from hydrocarbons
C01B 4/00
Hydrogen isotopes; Inorganic compounds thereof prepared by isotope exchange, e.g. NH3 + D2 → NH2D + HD [2006.01]
Halogens; Compounds thereof
Oxygen; Oxides or hydroxides in general; Per-compounds
C01B 23/00
Noble gases; Compounds thereof (liquefying F25J) [2006.01]
C01B 25/00
Phosphorus; Compounds thereof (C01B 21/00, C01B 23/00 take precedence; perphosphates C01B 15/16) [2006.01]
C01B 25/01
Treating phosphate ores or other raw phosphate materials to obtain phosphorus or phosphorus compounds [2006.01]
C01B 25/02
Preparation of phosphorus [2006.01]
C01B 25/023
of red phosphorus [2006.01]
C01B 25/027
of yellow phosphorus [2006.01]
C01B 25/04
Purification of phosphorus [2006.01]
C01B 25/043
of red phosphorus [2006.01]
C01B 25/047
of yellow phosphorus [2006.01]
C01B 25/06
Hydrogen phosphides [2006.01]
C01B 25/08
Other phosphides [2006.01]
C01B 25/10
Halides or oxyhalides of phosphorus [2006.01]
C01B 25/12
Oxides of phosphorus [2006.01]
C01B 25/14
Sulfur, selenium, or tellurium compounds of phosphorus [2006.01]
C01B 25/16
Oxyacids of phosphorus; Salts thereof (peroxyacids or salts thereof C01B 15/00) [2006.01]
C01B 25/163
Phosphorous acid; Salts thereof [2006.01]
C01B 25/165
Hypophosphorous acid; Salts thereof [2006.01]
C01B 25/168
Pyrophosphorous acid; Salts thereof [2006.01]
C01B 25/18
Phosphoric acid [2006.01]
C01B 25/20
Preparation from elemental phosphorus or phosphoric anhydride [2006.01]
C01B 25/22
Preparation by reacting phosphate containing material with an acid, e.g. wet process [2006.01]
C01B 25/222
with sulfuric acid, a mixture of acids mainly consisting of sulfuric acid or a mixture of compounds forming it in situ, e.g. a mixture of sulfur dioxide, water and oxygen [2006.01]
C01B 25/223
only one form of calcium sulfate being formed [2006.01]
C01B 25/225
Dihydrate process [2006.01]
C01B 25/226
Hemihydrate process [2006.01]
C01B 25/228
one form of calcium sulfate being formed and then converted to another form [2006.01]
C01B 25/229
Hemihydrate-dihydrate process [2006.01]
C01B 25/231
Dihydrate-hemihydrate process [2006.01]
C01B 25/232
Preparation by reacting phosphate containing material with concentrated sulfuric acid and subsequently lixiviating the obtained mass, e.g. clincker process [2006.01]
C01B 25/234
Purification; Stabilisation; Concentration (purification concomitant with preparation C01B 25/22; preparation involving solvent-solvent extraction C01B 25/46) [2006.01]
C01B 25/235
Clarification; Stabilisation to prevent post-precipitation of dissolved impurities [2006.01]
C01B 25/237
Selective elimination of impurities [2006.01]
C01B 25/238
Cationic impurities [2006.01]
C01B 25/24
Condensed phosphoric acids [2006.01]
C01B 25/26
Phosphates (perphosphates C01B 15/16) [2006.01]
C01B 25/28
Ammonium phosphates [2006.01]
C01B 25/30
Alkali metal phosphates [2006.01]
C01B 25/32
Phosphates of magnesium, calcium, strontium, or barium [2006.01]
C01B 25/34
Magnesium phosphates [2006.01]
C01B 25/36
Aluminium phosphates [2006.01]
C01B 25/37
Phosphates of heavy metals [2006.01]
C01B 25/38
Condensed phosphates [2006.01]
C01B 25/39
of alkali metals [2006.01]
C01B 25/40
Polyphosphates [2006.01]
C01B 25/41
of alkali metals [2006.01]
C01B 25/42
Pyrophosphates [2006.01]
C01B 25/44
Metaphosphates [2006.01]
C01B 25/445
of alkali metals [2006.01]
C01B 25/45
containing plural metal, or metal and ammonium [2006.01]
C01B 25/455
containing halogen [2006.01]
C01B 25/46
Preparation involving solvent-solvent extraction [2006.01]
C01B 31/00
Carbon; Compounds thereof (C01B 21/00, C01B 23/00 take precedence; percarbonates C01B 15/10; carbon black C09C 1/48) [2006.01]
C01B 31/02
Preparation of carbon (by using ultra-high pressure, e.g. for the formation of diamonds, B01J 3/06; by crystal growth C30B); Purification [2006.01]
C01B 31/04
Graphite [2006.01]
C01B 31/06
Diamond [2006.01]
C01B 31/08
Active carbon [2006.01]
C01B 31/10
Preparation by using gaseous activating agents [2006.01]
C01B 31/12
Preparation by using non-gaseous activating agents [2006.01]
C01B 31/14
Granulation [2006.01]
C01B 31/16
Preparation of ion-exchanging materials from carbonaceous material [2006.01]
C01B 31/18
Carbon monoxide [2006.01]
C01B 31/20
Carbon dioxide [2006.01]
C01B 31/22
Solidifying [2006.01]
C01B 31/24
Methods for the preparation of carbonates or bicarbonates in general (percarbonates C01B 15/10; particular individual carbonates, see the relevant groups of subclasses C01B-C01G, according to the cation) [2006.01]
C01B 31/26
Compounds containing carbon and sulfur, e.g. carbon disulfide, carbon oxysulfide; Thiophosgene [2006.01]
C01B 31/28
Phosgene [2006.01]
C01B 31/30
Carbides [2006.01]
C01B 31/32
Calcium carbide [2006.01]
C01B 31/34
Tungsten or molybdenum carbides [2006.01]
C01B 31/36
Carbides of silicon or boron [2006.01]
C01B 33/00
Silicon; Compounds thereof (C01B 21/00, C01B 23/00 take precedence; persilicates C01B 15/14; carbides C01B 31/36) [2006.01]
C01B 33/02
Silicon (forming single crystals or homogeneous polycrystalline material with defined structure C30B) [2006.01]
C01B 33/021
Preparation (chemical coating from the vapour phase C23C 16/00) [2006.01]
C01B 33/023
by reduction of silica or silica-containing material [2006.01]
C01B 33/025
with carbon or a solid carbonaceous material, i.e. carbo-thermal process [2006.01]
C01B 33/027
by decomposition or reduction of gaseous or vaporised silicon compounds other than silica or silica-containing material [2006.01]
C01B 33/029
by decomposition of monosilane [2006.01]
C01B 33/03
by decomposition of silicon halides or halosilanes or reduction thereof with hydrogen as the only reducing agent [2006.01]
C01B 33/031
by decomposition of silicon tetraiodide [2006.01]
C01B 33/033
by reduction of silicon halides or halosilanes with a metal or a metallic alloy as the only reducing agents [2006.01]
C01B 33/035
by decomposition or reduction of gaseous or vaporised silicon compounds in the presence of heated filaments of silicon, carbon or a refractory metal, e.g. tantalum or tungsten, or in the presence of heated silicon rods on which the formed silicon is deposited, a silicon rod being obtained, e.g. Siemens process [2006.01]
C01B 33/037
Purification (by zone-melting C30B 13/00) [2006.01]
C01B 33/039
by conversion of the silicon into a compound, optional purification of the compound, and reconversion into silicon [2006.01]
C01B 33/04
Hydrides of silicon [2006.01]
C01B 33/06
Metal silicides [2006.01]
C01B 33/08
Compounds containing halogen [2006.01]
C01B 33/10
Compounds containing silicon, fluorine, and other elements [2006.01]
C01B 33/107
Halogenated silanes [2006.01]
C01B 33/113
Silicon oxides; Hydrates thereof [2006.01]
C01B 33/12
Silica; Hydrates thereof, e.g. lepidoic silicic acid [2006.01]
C01B 33/14
Colloidal silica, e.g. dispersions, gels, sols [2006.01]
C01B 33/141
Preparation of hydrosols or aqueous dispersions [2006.01]
C01B 33/142
by acidic treatment of silicates [2006.01]
C01B 33/143
of aqueous solutions of silicates [2006.01]
C01B 33/145
Preparation of hydroorganosols, organosols or dispersions in an organic medium [2006.01]
C01B 33/146
After-treatment of sols (preparation of hydroorganosols, organosols or dispersions in an organic medium from hydrosols C01B 33/145) [2006.01]
C01B 33/148
Concentration; Drying; Dehydration; Stabilisation; Purification [2006.01]
C01B 33/149
Coating [2006.01]
C01B 33/151
by progressively adding a sol to a different sol, i.e. "build up" of particles using a "heel" [2006.01]
C01B 33/152
Preparation of hydrogels [2006.01]
C01B 33/154
by acidic treatment of aqueous silicate solutions [2006.01]
C01B 33/155
Preparation of hydroorganogels or organogels [2006.01]
C01B 33/157
After-treatment of gels [2006.01]
C01B 33/158
Purification; Drying; Dehydrating [2006.01]
C01B 33/159
Coating or hydrophobisation [2006.01]
C01B 33/16
Preparation of silica xerogels [2006.01]
C01B 33/18
Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof (treatment to enhance the pigmenting or filling properties C09C) [2006.01]
C01B 33/187
by acidic treatment of silicates [2006.01]
C01B 33/193
of aqueous solutions of silicates [2006.01]
C01B 33/20
Silicates (persilicates C01B 15/14) [2006.01]
C01B 33/22
Magnesium silicates [2006.01]
C01B 33/24
Alkaline earth metal silicates [2006.01]
C01B 33/26
Aluminium-containing silicates [2006.01]
C01B 33/32
Alkali metal silicates (C01B 33/26 takes precedence) [2006.01]
C01B 33/36
having base-exchange properties but not having molecular sieve properties [2006.01]
C01B 33/38
Layered base-exchange silicates, e.g. clays, micas or alkali metal silicates of kenyaite or magadiite type [2006.01]
C01B 33/40
Clays [2006.01]
C01B 33/42
Micas [2006.01]
C01B 33/44
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, e.g. organoclay material [2006.01]
C01B 33/46
Amorphous silicates, e.g. so-called "amorphous zeolites" [2006.01]
Compounds characterised primarily by their physical or chemical properties, rather than by their chemical constitution [6]