CPC Definition - Subclass C23F
This place covers:
Methods, compositions and apparatus for etching of metallic materials by chemical means (C23F 1/00 - C23F 1/44).
Regeneration of etching compositions, including apparatus for regenerating etching agents (C23F 1/46).
Methods, compositions and apparatus for chemical polishing (brightening) of metals (C23F 3/00 - C23F 3/06).
Other non-mechanical processes for removing metallic material from surfaces, e.g. by plasma or sputter etching, and compositions therefor (C23F 4/00 - C23F 4/04).
Simultaneous chemical and mechanical removal of metallic material from surfaces, e.g. by laser ablation (C23F 4/02, C23F 4/04).
Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion (C23F 11/00 - C23F 11/188).
Inhibiting corrosion of metallic material by adding inhibitors to the corrosive agent (C23F 11/00 - C23F 11/188).
Inhibiting corrosion of metals by anodic or cathodic protection (C23F 13/00 - C23F 13/22).
Inhibiting incrustation in apparatus for heating liquids for physical or chemical purposes (C23F 14/00), in polymerisation reactors (C23F 15/005).
Corrosion inhibitors per se (C23F 11/12 - C23F 11/18).
Incrustation inhibitors per se (C23F 14/02).
Other methods of preventing corrosion or incrustation, e.g. by removing the corrosive agent from the medium or rendering it non corrosive by neutralizing it (C23F 15/00).
Other apparatus for executing the methods mentioned above as far as they are specially adapted for treating metallic material, e.g. apparatus for regenerating etching agents; apparatus for anodic or cathodic protection, apparatus for executing the processes of the other groups, but only if they have at least one feature which is specifically designed for treating metallic material (C23F 1/00, C23F 3/00; C23F 4/00, C23F 13/00, C23F 14/00, C23F 15/00).
Multi-step processes for surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by subclass C21D or C22F or class C25 (C23F 17/00).
Protective layers or coating compositions or methods of applying them are not classified in this subclass but in the appropriate places, e.g. B05, B44, C09D, C10M, C23C.
Mechanical devices or constructional features of particular articles for inhibiting incrustation are not classified in this subclass but in the appropriate places, e.g. F16L pipes or pipe fittings.
Articles characterised by being made of materials selected for their properties of resistance to corrosion or incrustation are not to be classified in this subclass but in the appropriate places for such articles, e.g. F01D turbine blades.
This place does not cover:
Methods for preventing fouling | |
Working of metal by electro-erosion | |
De-surfacing by applying flames | |
Working metal by laser beam | |
Adding scale preventives or removers to water | |
Polishing compositions | |
Etching process and compositions for silicon or germanium | |
Adding corrosion inhibitors to pickling solutions | |
Electrolytic etching or polishing |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Preventing formation of scale in cooking vessels | |
Producing decorative effects by removing surface material, e.g. by engraving, by etching | |
Mechanical methods for preventing fouling in hull protection | |
Application corrosion inhibitors to containers, packaging elements, or packages, for contents presenting particular transport or storage problem | |
Manufacture or treatment of microstructural devices or systems in or on a substrate, e.g. MEMS devices, self-assembly devices, e.g. by etching | |
Preventing incrustations during destructive distillation of carbonaceous materials | |
Inhibition or prevention of corrosion or incrustation during processing of hydrocarbons | |
Use of additives to fuels or fires for minimising corrosion or incrustation | |
Adding corrosion inhibitors to lubricants | |
Measures against corrosion for turbine blades | |
Preventing incrustation in pipes | |
Manufacture of two-terminal components for integrated circuits, e.g. resistors, electrodes, capacitors, inductors by etching conductive layers |
Attention is drawn to the following places, which may be of interest for search:
Repairing fractures or cracked metal parts or products | |
Layered products comprising a layer of metal | |
Manufacture of printing surfaces | |
Surface treatment of glass by etching | |
Etching of natural or artificial stone or ceramics | |
Compositions for preventing, limiting or eliminating depositions | |
Compositions for in situ inhibition of corrosion in boreholes or wells | |
Etching, surface-brightening or pickling compositions in general, e.g. for silicon, metal nitrides, etc. | |
Regeneration of process liquids, e.g. of etching compositions | |
Portable water systems, e.g. treating plumbing systems for preventing leaching /elution of lead in water | |
Water supplying lines | |
In situ inhibition of corrosion in boreholes or wells | |
Preparing samples for investigations, e.g. by etching or polishing | |
Investigating or analysing metals by specific methods, e.g. metallographic etching | |
Photomechanical reproduction | |
Discharge tubes with the provision for introducing objects or materials to be exposed to the discharge, e.g. plasma apparatus and treatment in general (see C23F 4/00, classification rules) | |
Chemical or electrical treatment, e.g. by etching, of semiconductor bodies | |
After treatment of semiconductor bodies, e.g. by chemical mechanical polishing of conductive layers | |
After treatment of semiconductor bodies, e.g. by physical or chemical etching of conductive layers | |
Apparatus for treating semiconductor bodies | |
Manufacture of printed circuits |
C23F does not include methods, compositions and apparatus for treatment of non metallic material.
Groups C23F 1/00 - C23F 4/04 are not used for classifying methods, compositions and apparatuses for etching in general.
Classification of additional information
In many cases the classification of additional information is very useful for retrieving the document, and therefore very desirable, although not compulsory.
Well-disclosed and non-trivial aspects are classified.
Well-known (trivial) aspects or features are not classified.
For example:
If a document discloses an "etching process and composition for aluminium" (C23F 1/20), which in the description is also described as being suitable "for etching magnesium", and if this additional information is per se new /inventive ("non-trivial"), it is classified, namely C23F 1/22 as well.
In some cases the additional information is broadly defined as any secondary information useful for search that is not relevant per se, but that could be interesting for search when considered together with the important (invention-like) information, it is classified with (Indexing Code), e.g. "type of materials to be protected by cathodic protection (C23F 2201/00).
Subgroups and head groups
Apparatus or processes are classified in the subgroups for apparatus /process, if such subgroups exist, if not the process /apparatus are classified in the head group.
Etching /inhibiting compositions for are classified in the specific subgroups according to the intrinsic nature /function of the mixture or composition, e.g. acidic aqueous etching composition (C23F 1/16) or alkaline aqueous etching compositions (C23F 1/32).
An "application-oriented" invention should be classified in an application-oriented place (when it exists). An "application-oriented" invention is considered as:
- a thing "specially adapted for" a particular use or purpose, e.g. an apparatus modified or particularly constructed for etching /inhibiting corrosion or incrustation/ of metallic material;
- a particular use or application of a thing; e.g. alkaline composition for etching copper or alloys thereof (C23F 1/34).
If a document concerns embodiments which are covered by several subgroups (e.g. C23F 1/16 - C23F 1/30) dependent on a higher hierarchy group (head group, e.g. C23F 1/16), the following rules apply:
the specific technical information relevant for some of the subgroups is classified (EC) in all said subgroups;
if relevant, the combination of the elements covered by the subgroups is classified (EC) in the head group;
analogously, if generic technical information common to all of the subgroups is disclosed and only schematic embodiments of the specific subgroup embodiments are represented, the document is classified (EC) in the head group.
For example:
If a document discloses an acidic etching composition suitable for etching a metallic material in general, or selected from a big list of metals, without specific embodiments for the selected metals, then it is classified in the head group C23F 1/16;
If a document discloses an acidic etching composition for etching copper or alloys thereof, then it is classified in C23F 1/18;
In this place, the following terms or expressions are used with the meaning indicated:
Metallic material | covers metals and alloys |
Alloys | include: metallic composite materials containing a substantial proportion of fibres or other somewhat larger particles;ceramic compositions bonded by free metal, containing free metal bonded to carbides, diamond, oxides, borides, nitrides or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides or sulfides, other than as macroscopic reinforcing agents. |
Applying corrosion inhibitors | Applying corrosion inhibitors to a metallic surface layer is not considered to be applying a protective coating. |
Inhibiting corrosion | Inhibiting corrosion is a specific form of preventing corrosion, the words are not synonyms |
Corrosion | Deterioration of a metallic material due to a change of valence state caused by reactions with its environment. |
Incrustation | Accumulation of deposition /precipitation of undesired solid /dense products on a metallic surface in systems in which a fluid circulation takes place, preferably a water-based fluid, e.g. deposition /precipitation of compounds of calcium, magnesium, barium or strontium (carbonates/ sulphates, oxalates, phosphates, fluorides, silica, silicates, naphtelenates), iron /lead / zinc sulphide, zinc /cadmium carbonates (white rust). |
In patent documents, the following words/expressions are often used as synonyms:
- "incrustation", "crust" , "chalk", "limescale" and "carbonate /sulfate scale", "white rust"
- "etching", "stripping", "engraving"
In patent documents, the following words/expressions are often used with the meaning indicated:
"encrustation" | " incrustation". |
"fouling" | " incrustation" or "rusting". |
"chemical polishing" | "brightening". |
This place covers:
Methods, compositions and apparatus for etching of metallic materials by chemical means.
Regeneration of etching compositions, including apparatus for regenerating etching agents (C23F 1/46).
Selective etching /dealloying of an element /phase from an alloy in order to obtain a porous surface (C23F 1/00).
Selective etching of complex structures (i.e. metallic mutilayers) (C23F 1/44).
Local etching e.g. by using a photoresist mask (C23F 1/02).
Apparatus for photo-mechanical printing surface (C23F 1/08).
Emulsions compositions for etching of metallic material (C23F 1/42).
In the subgroup C23F 1/10, the expression "etching composition" is used with the meaning: "etching composition for specific metals" and covers: etching composition of specific metals, and not etching composition in general;
The subgroup C23F 1/06 relates to "sharpening files" (old technology).
Dry etching of semi-conductors are classified in H01L 21/00.
Processes of etching silicon used in semiconductors applications is classified in H01L 21/00.
Processes and compositions for etching silicon which are not for semiconductor applications are classified in C09K 13/00
This place does not cover:
Etching compositions of silicon or germanium | |
Electrolytic etching | |
Etching semiconductors |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Producing decorative effects by removing surface material, e.g. by engraving, by etching |
Attention is drawn to the following places, which may be of interest for search:
Manufacture of printing surfaces | |
Surface treatment of glass by etching | |
Etching of natural or artificial stone or ceramics | |
Recovering of metals from etching solutions | |
Regeneration of process liquids, e.g. of etching compositions | |
Repairing methods or devices for turbomachines | |
Cleaning of turbomachines | |
Photomechanical reproduction | |
Chemical etching of semiconductor bodies | |
Chemical etching of semiconductor bodies by using masks | |
After-treatment of conductive layers, e.g. by chemical liquid etching (wet-etching) | |
Semiconductor treating apparatus, e.g. for wet etching | |
Manufacture of printed circuits | |
Chemically removing of conductive material | |
Etching compositions | |
Improving adhesion between the insulating substrate and the metal by microetching |
The C23F1/24 IPC group is not used in the internal ECLA classification scheme. Subject-matter covered by this group is classified in the following groups: C09K 13/00 - C09K 13/08.
See the rules for classification of invention /additional information, and examples mentioned for the subclass C23F.
A selective etching composition of complex structures is classified in C23F 1/44 and the specific technical information relevant for some of the subgroups (C23F 1/14 - C23F 1/40) is classified in all said subgroups
For example:
If a document discloses an acidic etching composition for selectively etching a metal, such as Ta, from an aluminium substrate, then it is classified in the subgroups C23F 1/44 and C23F 1/26.
Processes of dry etching of metal materials by plasma are classified in C23F 4/00.
Processes of dry etching of metal materials by using gases are classified in C23F 1/12
In this place, the following terms or expressions are used with the meaning indicated:
Chemical Etching | Removal or dissolution of metallic material from a surface by chemical reaction between the metallic material and the etching agent |
Chemical Milling | Removal of high amount of metallic material from a piece having big dimensions by chemical reaction between the metallic material and the etching agent |
In patent documents, the following abbreviations are often used:
Etching | stripping, roughening, engraving, dulling, matting, wet-etching , dry-etching |
Dispersed water-immiscible liquid | powder less etching (old definition), emulsion, thixotropic etching |
This place covers:
Methods, compositions and apparatus for chemical polishing or chemical-mechanical (brightening) of metals.
Polishing (brightening) compositions receive an additional classification symbol in C09G (Polishing compositions other than French polish; ski waxes).
Apparatus receives an additional or only a classification symbol in B24B (Machines, devices, or processes for grinding or polishing).
This place does not cover:
Attention is drawn to the following places, which may be of interest for search:
Mechanical polishing apparatus, e.g. polishing pads | |
Polishing compositions | |
Abrasives, e.g. powders, suspensions, pastes for polishing | |
Surface-brightening compositions in general | |
After treatment of conductive layers, e.g. planarisation by chemical mechanical polishing | |
Polishing of the conductive pattern | |
Polishing for inhibiting the corrosion of the circuit, e.g. for preserving the solderability |
See the rules for classification of invention /additional information, and examples mentioned for the subclass C23F.
In this place, the following terms or expressions are used with the meaning indicated:
Chemical Polishing | Removal of metallic material from a surface in order to make the surface more bright by chemical reaction between the metallic material and the polishing agent |
Chemical-Mechanical Polishing (CMP) | Removal of metallic material from a surface by combining abrasive polishing and chemical polishing, typically by applying a polishing composition or slurry to a polishing pad, establishing pressure-contact between the composition-or slurry-coated surface and the polishing pad while providing relative motion, typically rotational or orbital motion, between the surface and the polishing pad. The chemically- mechanically polishing compositions typically contains an abrasive material, such as silica, ceria, and/or alumina particles, in an acidic, neutral, or basic solution. |
In patent documents, the following abbreviations are often used:
Chemical polishing | brightening |
Chemical-mechanical polishing (CMP) | planarization, smoothing, chemical-mechanical grinding, deburring |
Polishing compositions | polishing slurries |
Polishing | surface improvement |
Grinding | improvement of the dimensional accuracy |
This place covers:
Other non-mechanical processes for removing metallic material from surfaces, e.g. by plasma or sputter etching, and compositions therefor (C23F 4/00).
Removal of metallic material from surfaces, e.g. by evaporation /volatilisation /vaporisation (EP049312, GB998708, GB817017), e.g. CO2 or YAG lasers are utilized to thermally vaporize the metal layer, excimer laser for laser ablation, or in metal-halogen systems by laser stimulated halogen gas etching of metal substrates (US4622095, US5874011), or by using an UV light to produce a product which is either volatile or easily removed in solution (US4490211, US5318662) (C23F 4/02).
Removal of metallic material from surfaces, e.g. by physical dissolution /melting (EP0158536), by laser surface melting (EP1640109)(C23F 4/04).
This place does not cover:
Cleaning by radiant energy, e.g. by UV, laser, light beam | |
Cutting, scarfing or de-surfacing by applying flames, e.g. laser flame cutting | |
Working metal by laser beam, e.g. welding, cutting or boring metal parts by using plasma arc cutting torch, or a laser beam cutting head | |
Physical treatment to alter the texture of the surface, e.g. by irradiation with laser or particle beam | |
Etching semiconductors, e.g. by plasma |
Attention is drawn to the following places, which may be of interest for search:
Discharge tubes with the provision for introducing objects or materials to be exposed to the discharge, e.g. gas filled discharge tubes (plasma apparatus) | |
After treatment of conductive layers, e.g. by plasma etching | |
Apparatus or processes for manufacturing printed circuits, e.g. by the conductive material being removed by irradiation, |
The majority of documents to be classified in C23F 4/00 relate to removal of metallic material by plasma, which process is more physical than chemical.
Apparatus per se for dry etching are classified in H01J 37/00 and subgroups. If the apparatus has one feature specifically designed for treating metallic material, then the apparatus is also classified in C23F 4/00, e.g. plasma etching method and plasma etching apparatus for processing a magnetic film composed of iron or nickel.
In this place, the following terms or expressions are used with the meaning indicated:
Laser- induced chemical etching | Removal or dissolution of very thin layers of metallic material from a surface (in a very small amount) by reaction between the metallic material and reactive species (in the presence of reactive gases or under clean conditions) enhanced by incidence of a laser beam, e.g. by reaction of chlorine gas with aluminium is formed aluminium chloride which desorbs resulting in an etching of aluminium surface, the etching process of aluminium is further enhanced by UV laser pulses incident to the surface. |
Laser -induced ablation | Removal or dissolution of very thin layers of metallic material from a surface (in a very small amount) by evaporation or physical dissolution /dissociation under clean conditions by using an UV pulsed laser, e.g. an UV Excimer -Laser. |
Laser-transmissive ablation | A very thin metal film is selectively removed by means of a single radiation pulse. |
In patent documents, the following abbreviations are often used:
Plasma | discharge, DC, AC, RF, HF, UHF, MW, Hz, MHz, GHz, reactive ion etching, dry etching |
Laser | light (UV, IR) |
Evaporation | volatilisation, vaporization |
Laser -induced chemical etching | photoetching with laser as light source |
Laser -induced ablation | photoablation |
This place covers:
Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion.
Inhibiting corrosion of metallic material by adding inhibitors to the corrosive agent.
Preventing leaching /elution of a metallic element /phase from an alloy, e.g. in water systems (C23F 11/00).
Preventing leaching /elution of a metallic element /phase from an alloy, e.g. in water systems (C23F 11/08, C23F 11/10).
This place does not cover:
Adding corrosion inhibitors to pickling solutions |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Application corrosion inhibitors to containers, packaging elements, or packages, for contents presenting particular transport or storage problem | |
Adding corrosion inhibitors to deicing compositions | |
Adding corrosion inhibitors to antifreeze compositions | |
Flameproofing agents (also used as corrosion inhibitors) | |
Inhibiting or prevention of corrosion during processing of hydrocarbons | |
Use of additives to fuels or fires for minimising corrosion | |
Adding corrosion inhibitors to lubricants | |
Adding corrosion inhibitors to water systems, e.g. treating plumbing systems for preventing leaching/elution of metals in water |
Attention is drawn to the following places, which may be of interest for search:
Application corrosion inhibitors to containers, packaging elements, or packages, for contents presenting particular transport or storage problem | |
Adding corrosion inhibitors to deicing compositions | |
Adding corrosion inhibitors to antifreeze compositions | |
Compositions for in situ inhibition of corrosion in boreholes or wells | |
Compositions for treating boreholes or wells combined with additives added for specific purposes | |
Anti-oxidant compositions; Compositions inhibiting the chemical change | |
Flame-proofing agents (also used as corrosion inhibitors in alkaline solutions) | |
Inhibiting or prevention of corrosion during processing of hydrocarbons | |
Use of additives to fuels or fires for minimising corrosion | |
Adding corrosion inhibitors to lubricants | |
Adding corrosion inhibitors to pickling solutions | |
In situ inhibition of corrosion in boreholes or wells | |
Investigating resistance of metals to corrosion |
In the range C23F 11/12 - C23F 11/18, in the absence of an indication to the contrary, a compound is classified in the last appropriate place (last place rule).
In the head group C23F 11/00, the specific technical information is relevant to the method (process) of inhibiting corrosion, e.g. the way to apply the corrosion inhibitor, and not to the corrosion inhibitor composition.
In the subgroup C23F 11/02 the specific technical information is relevant to the method of adding volatile or vapour phase corrosion inhibitors (VpCI) to a enclosure, packaging (B65D 81/26), etc., for inhibiting the corrosion of a metallic material in air or a gases; VpCI corrosion inhibiting compositions per se.
In the subgroup C23F 11/04 the specific technical information is relevant to the method of inhibiting corrosion of metallic material in strong acidic solutions (pH ≤1), e.g. those used in acidic treatment of boreholes or wells (C09K 8/54).
In the subgroup C23F 11/06 the specific technical information is relevant to the method of inhibiting corrosion of metallic material in strong alkaline solutions (pH ≥14), e.g. those used in carbon dioxide capture systems.
In the subgroup C23F 11/08 the specific technical information is relevant to the method of inhibiting corrosion of metallic material in acidic or alkaline solutions comprising mixture of organic and inorganic inhibitors, e.g. in water systems, cooling systems, etc.
The salts of amines classified in C23F 11/143 (acid /alkaline) are also classified in C23F 11/08 or C23F 11/10.
In the subgroup C23F 11/10 the specific technical information is relevant to the method of inhibiting corrosion of metallic material in acidic or alkaline solutions comprising mixture of organic inhibitors, e.g. e.g. in water systems, cooling systems, etc.
In the subgroup C23F 11/18 the specific technical information is relevant to the method of inhibiting corrosion of metallic material in acidic or alkaline solutions comprising inorganic inhibitors.
In the subgroup C23F 11/187 the specific technical information is relevant to the method of inhibiting corrosion of metallic material in acidic or alkaline solutions comprising mixture of inorganic inhibitors.
In this place, the following terms or expressions are used with the meaning indicated:
Applying corrosion inhibitors | Applying corrosion inhibitors to a metallic surface layer is not considered to be applying a protective coating. |
Adding corrosion inhibitors | Adding corrosion inhibitors to a corrosive agent (composition) is always in a small amount, which makes a big difference between a corrosion inhibiting composition and a protective coating composition |
In patent documents, the following abbreviations are often used:
Iron corrosion inhibitor | deruster |
Corrosion inhibitor | metal ions complexer/chelator/sequestrant |
This place covers:
Methods, apparatuses and electrode materials for inhibiting corrosion of metals by anodic or cathodic protection, i.e. for applying a current and polarizing a metallic object /structure to be protected while the object /structure is in use.
A system of particles in a paint layer classified in C09D 5/00 receives an additional classification symbol in C23F 13/06 as far as the combination of particles and paint constitute an assembly for cathodic protection (i.e. is acting as anode for cathodic protection of a metal).
Controlling /regulating process and device for electrochemical measuring of corrosion or corrosion - protection measurement classified in G01N 17/02 receives an additional classification symbol in C23F 13/04 as far as they contain a parameter of the cathodic protection process.
This place does not cover:
Anodisation | |
Reinforcing elements, e.g. for concrete : Anti-corrosion | |
Coatings or treating compositions |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Electrochemical re-alcalisation, e.g. when the same device is used to apply cathodic protection and re-alcalisation, either sequently or simultaneously | |
Electrochemical desalination, e.g. when the same device is used to apply cathodic protection and desalination, either sequently or simultaneously | |
Cathodic protection of reinforced concrete structure | |
Means for protecting offshore constructions against corrosion, e.g. by cathodic protection | |
Arrangements for filling cracks or cavities in building constructions, e.g. cathodic protection assemblies used as well for such arrangements | |
Corrosion preventing means for features common to bolt and nuts, e.g. cathodic protection assemblies | |
Cathodic protection for water heaters | |
Electrochemical measuring systems for weathering, corrosion or corrosion protection measurements, e.g. cathodic protection measurements |
Attention is drawn to the following places, which may be of interest for search:
Component parts, detail or accessories for large containers | |
Compositions of mortars, concrete, artificial stone, containing inorganic binders | |
Anti-corrosive paints | |
Anti-corrosive paints containing metal dust | |
Anti-corrosive paints containing Al dust | |
Anti-corrosive paints containing Zn dust | |
Electrically conductive paints | |
Arrangements or adaptation of tanks for water supply | |
Reinforced concrete | |
Component parts of turbines for preventing corrosion | |
Investigating or analysing concrete or cement by specific methods | |
Intrinsically conductive polymers |
An ionic conductor as such (e.g. composition) is classified in C23F 13/02 since the ionic conductor constitutes a selection of ionic conductivity condition.
The integration of an ionic conductor in a cathodic protection system is classified in C23F 13/06 since the specific technical information relevant is the combination of the ionic conductor with other elements of the cathodic protection device.
In both cases, the KW cp ionic (C23F) has to be given to the document.
A system of particles in a paint layer (C09D 5/00) acting as anode for cathodic protection of a metal is classified in C23F 13/06 since the combination of particles and paint constitute an assembly for cathodic protection.
An electrode made of a layer directly deposited on the metal to be protected is classified in C23F 13/08.
Monitoring arrangements for electrodes, e.g. wear indicators, alarms, are classified in C23F 13/22.
C23F 2201/00 covers cathodic protection assemblies and processes in which specific material is protected by cathodic protection, i.e. when the assembly or process is specifically designed to protect a given material.
C23F 2201/02 covers any aspects of cathodic protection assemblies and processes which are specially adapted to protect reinforcement in concrete.
In this place, the following terms or expressions are used with the meaning indicated:
Anodic protection (AP) | Technique to control the corrosion of a metal surface by making it the anode of an electrochemical cell and controlling the electrode potential in a zone where the metal is passive. |
Cathodic protection (CP) | Technique to control the corrosion of a metal surface by making it the cathode of an electrochemical cell |
Sacrificial anode | A piece of corrodible metal, attached to a metallic surface to be protected, that is preferentially consumed by electrolytic action. |
Stray currents | Stray currents may originate from direct-current distribution lines, substations, or street railway systems, etc., and flow into a pipe system or other steel structure. |
In patent documents, the following abbreviations are often used:
Ionic conductor | backfill, grout, hydratant, humectant, electrochemical activating agent |
In patent documents, the following words/expressions are often used as synonyms:
- "sacrificial anode", "galvanic anode" and "active anode"
This place covers:
Inhibiting incrustation in apparatus for heating liquids for physical or chemical purposes, e.g. evaporators, distillations units, crystallisation units, etc. (C23F 14/00).
Inhibiting incrustation by chemical means and incrustation inhibitors per se (C23F 14/02).
Other apparatus for executing the methods mentioned above as far as they are specially adapted for treating metallic material (C23F 14/00).
This place does not cover:
Methods for preventing fouling | |
Adding scale preventives or removers to water |
Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:
Preventing formation of scale in cooking vessels | |
Treatment of water, waste water or sewage | |
Preventing incrustations during destructive distillation of carbonaceous materials | |
Inhibiting or prevention of corrosion or incrustation during processing of hydrocarbons | |
Preventing incrustation in pipes |
Attention is drawn to the following places, which may be of interest for search:
Anodic or cathodic protection | |
Evaporating | |
Distillation | |
Crystallisation | |
Treatment of water, waste water or sewage | |
Composition for preventing, limiting or eliminating depositions | |
Composition for preventing, limiting or eliminating inorganic depositions, e.g. sulfates or carbonates | |
Preventing the formation of deposits or corrosion, e.g. by using filters |
In the head group C23F 14/00, the specific technical information is relevant to the method (process) of inhibiting incrustations in apparatuses for heating liquids for physical or chemical purposes
In the subgroup C23F 14/02 the specific technical information is relevant to the method for preventing or removing scale formation in systems in which a fluid circulation, preferably a water-based fluid circulation takes place, by adding chemical incrustation inhibitors to the system; Incrustation inhibiting compositions per se.
The expression "inhibiting incrustation in general" is used with the meaning:
"inhibiting incrustation of metallic material " and covers: a particular purpose (application), that of inhibiting incrustation of metallic material, and not inhibiting incrustation general;
and this for two reasons:
first of all incrustation "process for forming a tenacious crust" is mainly a property of the environment where an object is placed and hardly a property of the material from which the object is made; inhibiting incrustation in general should thus be better classified in the process where the problem occurs (e.g. C02F).
secondly to make the difference with fouling "accumulation of particulates of microorganisms on the surface" classified in B08B 17/00. Moreover, the term fouling is very broad and appears to cover also processes as "rusting" (C23F 11/00) and "formation of scale" (C02F).
In this place, the following terms or expressions are used with the meaning indicated:
Incrustation of metallic material | Accumulation of deposition /precipitation of undesired solid /dense products on a metallic surface in systems in which a fluid circulation takes place, preferably a water-based fluid circulation takes place, e.g. deposition /precipitation of compounds of calcium, magnesium, barium or strontium (carbonates/ sulphates), iron, lead, zinc sulphide, zinc, cadmium carbonates (white rust). |
In patent documents, the following abbreviations are often used:
Incrustation | encrustation, crust, carbonate/sulphate scale, lime scale, sulphide scale, aluminosilicate scale, oxalate scale., white rust. |
In patent documents, the following words/expressions are often used with the meaning indicated:
"inhibiting incrustation in general" | "inhibiting incrustation of metallic material " |
This place covers:
Other methods of preventing corrosion or incrustation, e.g. by removing the corrosive agent from the medium or rendering it non corrosive by neutralizing it (C23F 15/00).
Inhibition incrustations, e.g. in polymerization reactors (EP1501910), in waste liquid line of an autoanalyzer (EP1477811) (C23F 15/005).
Other apparatus for executing the methods mentioned above as far as they are specially adapted for treating metallic material (C23F 15/00).
This place does not cover:
Methods for preventing fouling |
Attention is drawn to the following places, which may be of interest for search:
Inhbiting corrosion of metals by anodic or cathodic protection | |
Evaporating | |
Distillation | |
Crysatllization | |
Processes of separation, e.g. by filtration, ultrafiltration, dialysis, osmosios | |
Chemical, physical, or physico-chemical processes carried out with a view to control or to change the pH- value; Application of buffer salts; Neutralisation reactions | |
Mechanical methods for preventing fouling in hull protection | |
Treatment of water, waste water, or sewage by degassing (liberation of dissolved gases) | |
Treatment of water, waste water, or sewage by electrochemical methods for prevention or elimination of deposits | |
Treatment of water, waste water, or sewage with magnetic or electric field for prevention or elimination of deposits | |
Treatment of water, waste water, or sewage by addition of specified substances, e.g. by addition of complex-forming compounds | |
Treatment of water, waste water, or sewage by oxidation | |
Preventing scale by precipitation of the hardness | |
Compositions for preventing, limiting or eliminating depositions | |
Anti-oxidant compositions; Compositions inhibiting the chemical change | |
Preventing or removing incrustations in thermal non-catalytic cracking | |
Inhibiting corrosion or fouling in apparatus for treatment or conversion of hydrocarbon oils | |
Use of additives to fuels or fires for minimising corrosion or incrustation | |
Means for protecting offshore constructions against corrosion | |
Devices and methods for diminishing corrosion in steam boilers | |
Preventing the formation of deposits or corrosion in heta-exchangers , e.g. by protective currents |
A clear difference has to be made between the word "fouling" with the above meanings and the word "fouling" used with the meaning " accumulation of particulates of microorganisms of the surface" classified in B08B 17/00.
A clear difference has to be made between the word "scale" with the above meaning and the word "scale" used with the meaning "white rust" "staining", "incrustation" "carbonate, sulphate, sulphide, silicate, oxalate scale" or "hydrocarbon scale" classified in C23F 14/00, C23F 15/00.
In patent documents, the following words/expressions are often used with the meaning indicated:
"fouling" | " incrustation" or "rusting". |
"scale" | "rust" or " scale from ferrous metals, copper or aluminium alloys" or "rust staining". |
This place covers:
This place does not cover:
Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of main groups C23C 2/00 - C23C 26/00, or by combinations of methods provided for in subclasses C23C and C25D |
Attention is drawn to the following places, which may be of interest for search:
Modifying the physical structure of ferrous metals; General devices for heat treatment of ferrous or non-ferrous metals or alloys; making metals malleable by decarburisation, tempering or other treatment | |
Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working | |
After-treatment of hot-dipped or immersed coated metal surfaces | |
After-treatment of sprayed coated metal surfaces | |
Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, e.g. diffusion coatings | |
After-treatment of vacuum evaporated coated metal surfaces | |
After-treatment of chemical vapour deposited coated metal surfaces | |
After-treatment of electroplated surfaces |
The majority of documents classified in C23F 17/00 are also classified with at least one of the above mentioned subclasses /groups. In many cases the classification of invention information is only classified in the most appropriate place, namely, in only one of these subclasses /groups, with no need to also classify in C23F 17/00. This practice is very desirable, although not compulsory. As far as the combination of process steps defined as in the title of C23F 17/00 is important (invention-like information), these documents belong also in this class.