Cooperative Patent Classification


CPC Definition - Subclass C09K

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Last Updated Version: 2017.08
MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
Definition statement

This place covers:

The use of materials for applications not provided for elsewhere, e.g. sealing materials, drilling fluids.

The use of materials in general having specific properties, not provided for elsewhere, e.g. anti-static properties, anti-oxidation properties.

Materials selected for uses or applications not provided for elsewhere.

All entries in this subclass relate to specific properties (e.g. C09K 3/16 relates to materials with anti-static properties) or specific applications of materials (e.g. C09K 17/00 relates to soil-conditioning or soil-stabilizing materials), except for main group C09K 3/00 itself, which is the residual place for classifying materials with properties or applications for which no entries exist in C09K itself nor elsewhere in IPC.

References
Limiting references

This place does not cover:

Materials or their applications or uses for which entries are available elsewhere in IPC.

References out of a residual place

Examples of places in relation to which this place is residual:

e.g. preparations for medical, dental, or toilet purposes

e.g. sorbent compositions or catalysts

B01

Chemical treatment of wood or similar materials

inorganic chemistry

C01

organic chemistry

C07

organic macromolecular compounds and their compositions

C08

Coating compositions, e.g. paints

Fuels

Applications of materials relating to photography, cinematography and analogous techniques

G03

Selection of materials for their conductive, insulating, or dielectric properties

Selection of materials for piezo-electric materials

Selection of materials for electrochemical generators, e.g. batteries

Applications of materials relating to agriculture, foodstuffs, medical or cosmetic preparations,

A

Applications of materials relating to physical or chemical processes in general,

B

Pure chemistry, which covers compounds and their methods for preparation:

Applications of materials relating to fibrous materials, textiles or paper

D

Applications of materials relating to electric or electronic elements

H

Informative references

Attention is drawn to the following places, which may be of interest for search:

Solid sorbent compositions

Materials for treatment of water, waste water, or sewage

Fertilisers,

C05

e.g. mixtures of soil-conditioning or soil-stabilising materials with fertilisers characterised by their fertilising activity

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Materials

include compounds, compositions, mixtures and preparations

Materials not provided for elsewhere
Definition statement

This place covers:

Only materials for which no specific application is mentioned, for example thickeners that can be used for any composition are classified in this class .

Relationships with other classification places

Compositions for which an application is mentioned i.e. an application class is available , the documents are classified in the relevant application class only , for example: thickener for food A23, for cosmetics A61, for paints C09D.

{Materials in mouldable or extrudable form} for sealing or packing joints or covers (filling pastes C09D 5/34)
Definition statement

This place covers:

Material in extrudable or mouldable form used for sealing or packing joints or covers

Relationships with other classification places

C09K relates to materials not provided elsewhere,

therefore

If the sealant is only claimed with regard to a specific application and if in said specific application field a class related to the chemical nature of the sealant exists the document should only be classified in the application field

e.g.:

B29C 73/16 (tyre puncture sealing)

B60R 13/06 (sealing strips)

C09K 8/50-C09K 8/518 (sealing or packing boreholes or wells)

References
Limiting references

This place does not cover:

Lime, cements, mortars

Filling pastes

Adhesives

Informative references

Attention is drawn to the following places, which may be of interest for search:

Use of inorganic ingredients

Use of organic ingredients

Compositions of macromolecular compounds

Special rules of classification

If no specific application of the sealant is cited, the document should only be classified in the appropriate C09K 3/10 class.

If the sealant is claimed without specific uses the document should be classified in the appropriate C09K 3/10 class,

however

If specific applications are cited (e.g. in the description) the document should additionally be classified in the relevant application fields

and

if many different applications are cited the document should only be classified in the appropriate C09K 3/10 class.

C09K 3/1006 is not used for classification.

All documents not falling under the definition of C09K 3/1003 or in the range C09K 3/1009 - C09K 3/1021 should be classified in C09K 3/10

Classification of additional information is done by using Indexing Codes:

for indexing the properties and uses of the material : C09K 3/10 - C09K 2003/1096

for indexing the chemical nature of the material: C09K 2200/00 - C09K 2200/0697

Anti-slip materials; Abrasives {(products specifically intended for the fabrication of abrasive tools, blocks or papers, or for operations of the kind of sand-blasting and barrelling B24B 31/14, B24C 1/00; polishing compositions containing abrasive or grinding agents C09G 1/02; polishing of semi-conductors H01L; friction compositions for brakes or clutches F16D 69/02)}
References
Limiting references

This place does not cover:

Products specifically intended for the fabrication of abrasive tools, blocks or papers, or for operations of the kind of sand-blasting and barrelling

Polishing compositions containing an abrasive which is not specific or polishing compositions WITHOUT abrasive

Polishing compositions containing abrasive or grinding agents

Polishing of semi-conductors H01L; friction compositions for brakes or clutches

Informative references

Attention is drawn to the following places, which may be of interest for search:

Abrasives as fillers for polymers

Cleaning or scraping pads

Lapping

Polishing of glass

Polishing of metals

products specifically intended for the fabrication of abrasive tools, blocks or papers, or for operations of the kind of sand-blasting and barrelling

Sawing fluids e.g. of silicon ingots, precious stones

Tools, grinding wheels

; polishing compositions containing abrasive or grinding agents

polishing of semi-conductors

friction compositions for brakes or clutches

Special rules of classification

In this class boron and silicon are considered as metals , as well as association of carbon with metals e.g. carbides . Particles coated with boron , silicon or carbides : C09K 3/1445

{Abrasive particles per se (preparation of diamond C01B 32/25)}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Preparation of particles in general

Abrasive particles for sand blasting

Preparation of diamond

Abrasives particles as fillers for polymers

{Abrasive powders, suspensions and pastes for polishing}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Lapping

Sawing fluids e.g. of silicon ingots, precious stones

Polishing of glass

Methods and processes for polishing semi-conductors

Polishing of semi-conductors

Anti-static materials
References
Limiting references

This place does not cover:

Conductive materials

Informative references

Attention is drawn to the following places, which may be of interest for search:

Antistatic paper

Photo paper

for application to surfaces to minimize adherence of ice, mist or water thereto (rendering particulate materials free flowing, in general, e.g. making them hydrophobic B01J 2/30); Thawing or antifreeze materials for application to surfaces (used in liquids for heat-transfer, heat-exchange or heat-storage or for the production of heat or cold other than by combustion, e.g. radiator liquids, C09K 5/00)
Definition statement

This place covers:

Compositions for non permanent treatment, with no formation of a permanent coating in order to reduce attachment of ice, mist or water to surfaces

Relationships with other classification places

A permanent coating, film on a surface is classified in C09D, e.g. water based barrier cohesive film

References
Limiting references

This place does not cover:

Used in liquids for heat-transfer, heat-exchange or heat-storage or for the production of heat or cold other than by combustion, e.g. radiator liquids,

Rendering particulate materials free flowing, in general, e.g. making them hydrophobic

Permanent coating ( polymer -> film)

Informative references

Attention is drawn to the following places, which may be of interest for search:

Treatment of agricultural products

Process for dewatering

Treatment of bulk material e.g. sand or coal

Glass surfaces

Dewatering of surfaces

Treatment of textiles

for dust-laying or dust-absorbing
Definition statement

This place covers:

Compositions for non-permanent treatment in order to have dust-laying or dust absorbing

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Treatment of fertilisers in powder form

Treatment of road surfaces

Treatment of mines

Treatment of tunnel walls

for simulating ice or snow
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Artificial surfaces for winter sports

Fabrication of Ice or snow for sports

for aerosols (aerosol containers B65D 83/14)
Definition statement

This place covers:

Chemical compounds and mixtures of chemical compounds for aerosols, e.g. propellants

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Sprayers for therapeutic purposes

Inhalators

Aerosol containers

for absorbing liquids to remove pollution, e.g. oil, gasoline, fat
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Litters for animals

Solid sorbents

Treatment of water

Apparatus for removing oil from water

Heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants; Materials for the production of heat or cold by chemical reactions other than by combustion
Definition statement

This place covers:

Materials undergoing a change of physical change when used

Materials not undergoing a change of physical change when used

Materials undergoing chemical reactions when used

Antifreeze additives

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Arrangement or adaptations of heating, cooling, ventilating, or other air-treating devices specially for passenger or goods spaces of vehicles

Lubricating compositions

Corrosion inhibitors

Use of solar heat; selection of specific heat-exchange medium

Refrigeration machines, plants or systems, combined heating and refrigeration systems; heat systems

Heat-exchange apparatus

Details of heat-exchange and heat-transfer apparatus, of general application

Special rules of classification

Last place rule applies

When classifying in C09K 5/042, C09K 5/044 and C09K 5/045 classification of additional information is done by using Indexing Codes:

for indexing the chemical nature of the material: C09K 2205/00 - C09K 2205/48

The subgroups of C09K 5/08 might be incomplete as some of the patent documents classified in C09K 5/08 might need reclassification to one or more groups C09K 5/10 - C09K 5/14

The group C09K 5/18 might be incomplete as some of the patent documents classified in C09K 5/16 might need reclassification to C09K 5/18

Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
References
Limiting references

This place does not cover:

Oil recovery from bituminous sands

C10G31/04

Special rules of classification

C09K 8/02 - C09K 8/38 : Last Place Rule

Drilling fluids with fluid loss additives : C09K 8/02-C09K 8/38 and C09K 8/50-C09K 8/536

when appropriate use Indexing Code for "spotting" and E21B 31/03

Synonyms and Keywords

Spotting fluids

Fluids for releasing stuck drill string

Specific additives for general use in well-drilling compositions
Definition statement

This place covers:

Only when the additive as such is disclosed without specification of the drilling fluid OR if it is for any kind of drilling fluid : C09K 8/03-C09K 8/035

Special rules of classification

mixtures of inorganic and organic additives : C09K 8/03 only

{characterised by the composition of the clay}
Definition statement

This place covers:

Aqueous well-drilling compositions characterised by well defined clay composition

Relationships with other classification places

Organoclays per se are classified in C01B 33/44

Drilling fluids comprising organoclays will be classified in C09K 8/145 and C01B 33/44

References
Limiting references

This place does not cover:

organoclays per se : C01B 33/44

Synthetic organic compounds
Definition statement

This place covers:

Monomers

Organic liquids
Definition statement

This place covers:

Specific non- oil components , e.g. olefins ,paraffins , special environmently friendly components

Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells (compositions for plastering C09K 8/50)
References
Limiting references

This place does not cover:

Well-drilling compositions

Compositions for plastering borehole walls

Proppants

Sealing or packing boreholes or wells

Special rules of classification

Documents classified in C09K 8/42 and subgroups receive also a class and CIS codes in C04B in order to define the cementitious composition in more detail.

Multiple classes can be used where appropriate.

Compositions for plastering borehole walls, i.e. compositions for temporary consolidation of borehole walls (compositions for consolidating loose sand or the like around wells C09K 8/56)
Definition statement

This place covers:

Temporary seal , sealing for control of water flow in or out the formation, fluid loss control, profile modification

References
Limiting references

This place does not cover:

Permanent seal for e.g. killing/closing a well

Compositions for consolidating loose sand or the like around wells

Special rules of classification

- No last place rule in C09K 8/50 - C09K 8/94,multiple classification when appropriate

- When appropriate : use Indexing Code for fibers

Synonyms and Keywords

In patent documents, the following words/expressions are often used as synonyms:

  • "fluid loss control" , "filtration control", "profile control" and "temporary sealing"
characterised by their form or by the form of their components, e.g. encapsulated material
Special rules of classification

For fibers : use Indexing Code

Compositions for preventing, limiting or eliminating depositions, e.g. for cleaning
Definition statement

This place covers:

Compositions for use in the well also for removing drilling residues

Cleaning is also called remediation

Relationships with other classification places

Compositions for use in the pipes F17D

Special rules of classification

- No last place rule in C09K 8/52 - C09K 8/536 , multiple classification needed if material incorporated in characteristic form.

- Compositions for removing drilling residues : C09K 8/52

- For preventing formation of hydrates formation C09K 8/52 and Indexing Code for "hydrates inhibition"

-Compositions for removing /preventing specific depositions C09K 8/524-C09K 8/532

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Cleaning

remediation

Sulfur
Definition statement

This place covers:

Also sulfides

Special rules of classification

For H2S use corresponding Indexing Code

Compositions for in situ inhibition of corrosion in boreholes or wells
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Corrosion inhibitors as such

Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids
Definition statement

This place covers:

secondary and tertiary recovery

References
Limiting references

This place does not cover:

Injection of Carbon dioxide alone

Method/Process for enhanced recovery

Informative references

Attention is drawn to the following places, which may be of interest for search:

Surfactants as such

Bacteria

Special rules of classification

- No last place rule in C09K 8/58-C09K 8/594, multiple classification might be needed

- Viscolelastic surfactants : Indexing Code for VES

characterised by the use of bacteria
Definition statement

This place covers:

also enzymes

Relationships with other classification places

Bacteria as such : C12P, C12R

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

MEOR

Enhanced oil recovery using bacteria

characterised by the use of specific surfactants
Definition statement

This place covers:

also polymeric surfactants

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Surfactants as such

Special rules of classification

Indexing Code for VES (viscoelastic surfactants )

Compositions used in combination with injected gas {, e.g. CO2 orcarbonated gas} (C09K 8/592 takes precedence)
References
Limiting references

This place does not cover:

N: e.g. CO2 or carbonated gas

Injection of CO2 alone

Compositions for stimulating production by acting on the underground formation
References
Limiting references

This place does not cover:

Methods for stimulating production

Special rules of classification

Details of composition: C09K 8/84 - C09K 8/88

{containing surfactants}
Definition statement

This place covers:

also demulsifiers surfactants

{specially adapted for clay formations}
Definition statement

This place covers:

capillary imbibition

Compositions for forming crevices or fractures
References
Limiting references

This place does not cover:

Gas fracturing

Methods for forming fractures or crevices

Methods for reinforcing fractures by propping

Special rules of classification

C09K 8/62 should be used in combination with the classes for specific components

{containing inorganic compounds (proppants C09K 8/80)}
Definition statement

This place covers:

gel breakers

containing organic compounds
Definition statement

This place covers:

monomers and polymers

References
Limiting references

This place does not cover:

Proppants

Methods for fracturing

Special rules of classification

- defined polymers C09K 8/68 and classes C09K 8/88-C09K 8/905

- defined surfactants ,C09K 8/68 and class C09K 8/602 and Indexing Code for viscoelastic surfactants (VES) when appropriate.

-organic gel breakers : C09K 8/68 and Indexing Code for " gel breaker" or "bacteria or enzyme breaker"

characterised by their form or by the form of their components, e.g. foams
Definition statement

This place covers:

also gas

{Encapsulated breakers}
Definition statement

This place covers:

also breakers with any coating which delays the action of the breaker (i.e. also surfactant around the particles)

Eroding chemicals, e.g. acids
Definition statement

This place covers:

acid fracturing - acidizing, - fracture acidizing- matrix acidizing

References
Limiting references

This place does not cover:

Use of weak acids for cleaning without creating crevices

Special rules of classification

Acidizing in combination with drilling , C09K 8/72 and C09K 8/02

combined with additives added for specific purposes
Definition statement

This place covers:

- corrosion inhibitors

- surfactants

- breakers

Special rules of classification

when appropriate, use Indexing Codes for :

- anticorrosion

- Viscoelastic surfactant (VES)

- "gel breaker" or "bacteria or enzyme breaker"

for preventing sealing
Definition statement

This place covers:

Anti-sludge additives

Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
Definition statement

This place covers:

Compositions for consolidating fractures and compositions of proppants

References
Limiting references

This place does not cover:

Fabrication of inorganic particles

Specific inorganic materials

C01

Fabrication of organic particles

Methods for reinforcing fractures by propping

characterised by their form or by the form of their components, e.g. encapsulated material (C09K 8/70 takes precedence)
Definition statement

This place covers:

also gas

References
Limiting references

This place does not cover:

encapsulated material

Tenebrescent materials, i.e. materials for which the range of wavelengths for energy absorption is changed as result of excitation by some form of energy ({liquid crystal materials C09K 19/00; photochromic glass C03C 4/06; in thermometers G01K 11/12; in photochromic filters G02B 5/23; in optical modulation devices G02F 1/00} ; photosensitive materials for photographic purposes G03C; {in cathodochromic screens H01J 29/14})
Definition statement

This place covers:

Tenebrescent materials, i.e. materials for which the range of wavelength for energy absorption is changed as result of excitation by some form of energy

Relationships with other classification places

Photosensitive materials for photographic purposes G03C

References
Limiting references

This place does not cover:

Liquid crystal materials

Photochromic glass

In thermometers

In photochromic filters

In optical modulation devices

Materials in cathodochromic screens

Informative references

Attention is drawn to the following places, which may be of interest for search:

Luminescent materials

Special rules of classification

Markush formulae or generic formulae are not classified, only concrete embodiments or examples are classified. Simple lists of known compounds (without application in an example or embodiment) are not classified.

C09K 9/02 (organic tenebrescent materials), C09K 11/06 (organic phosphors)

The respective Indexing Code-codes (range C09K 2211/00) for specific organic compounds have to be applied for all newly classified documents.

The documents have to be circulated to the corresponding classifiers in organic chemistry or polymers.

Other neighbouring fields should receive the document if an application in the respective field is mentioned (e.g. semiconductors, markers in biotechnology).

The last-place rule is strictly applied (no double classification in the main group and the respective sub-groups).

Markush formulae or general formulae are not classified, only concrete embodiments or examples.

Luminescent, e.g. electroluminescent, chemiluminescent materials
Definition statement

This place covers:

Luminescent materials, i.e. materials emitting light after excitation by some form of energy in the form of e.g. electrical energy, chemical energy, radiation in the visible, ultraviolet, X-ray or gamma-ray range

References
Limiting references

This place does not cover:

Liquid crystal materials

Informative references

Attention is drawn to the following places, which may be of interest for search:

Tenebrescent materials

Special rules of classification

Markush formulae or generic formulae are not classified, only concrete embodiments or examples are classified. Simple lists of known compounds (without application in an example or embodiment) are not classified.

C09K 11/06 (organic phosphors)

The respective Indexing Code (range C09K 2211/00) for specific organic compounds have to be applied for all newly classified documents.

The documents have to be circulated to the corresponding classifiers in organic chemistry or polymers.

Other neighbouring fields should receive the document if an application in the respective field is mentioned (e.g. semiconductors, markers in biotechnology).

C09K 11/08 and subgroups (inorganic phosphors):

all elements in the inorganic compounds are used to determine the position in the scheme including the doping materials (Si,Al)(O,N) SiAlON, SiN, AlN phosphors are classified under the respective subclasses dealing with silicates/aluminates (e.g.C09K 11/7721, C09K 11/7734 etc.) and additionally under C09K 11/0883, in order to classify the nitride. A silicate and aluminate is a compound containing a silicion and/or aluminium atom and an anion. Under this definition nitrides ((Si,Al)(O,N)), fluorides (e.g.K2SiF6), sulfides (e.g. BaAl2S4) are considered as silicates/aluminates.

In all other cases the last-place rule is strictly applied (no double classification in the main group and the respective sub-groups).

Markush formulae or general formulae are not classified, only concrete embodiments or examples.

Magnesium is considered as an earth alkali metal for the purpose of this classification scheme.

Etching, surface-brightening or pickling compositions (for glass C03C 15/00, {C03C 25/66; for mortars, concrete, artificial or natural stone or ceramics C04B 41/5338} ; for metallic material C23F, C23G 1/00, C25F 1/00; {for semi-conductors H01L})
Definition statement

This place covers:

Also covers etching of silicon and germanium

References
Limiting references

This place does not cover:

Etching of glass

for glass

For mortars, concrete, artificial or natural stone or ceramics

Etching of polymers

Polishing compositions

for metallic material

Etching of metals

Methods for etching semi-conductors

Special rules of classification

Last place rule is to be applied

Anti-oxidant compositions; Compositions inhibiting chemical change ({for use in well-specified applications, see the relevant places, e.g. in etching or pickling compositions C09K 13/00, C23G} , in foodstuffs A21D, A23, {in association with organic compounds C07C, C07D} , in macromolecular compositions C08; in liquid fuels or lubricants C10; in fats, fatty substances, fatty oils or waxes C11B 5/00; in detergents C11D; {coating or impregnating carbon or graphite based bodies to protect them from oxidation C04B 41/45} ; corrosion inhibiting compositions for metallic material C23F 11/00)
Definition statement

This place covers:

also UV absorbers

References
Limiting references

This place does not cover:

In foodstuffs

Compositions for preserving food

Oxygen scavengers in packaging materials

Coating or impregnating carbon or graphite based bodies to protect them from oxidation

In association with organic compounds

In macromolecular compositions

C08

In liquid fuels or lubricants

C10

In fats, fatty substances, fatty oils or waxes

In detergents

Corrosion inhibiting compositions for metallic material

Special rules of classification

- anti-oxidised compositions : classified according to the composition itself

- inhibited compositions

In C09K 15/00 - C09K 15/34 : Last Place Rule

Deviation from IPC definition : In present class a metallic salt or complex is classified in C09K 15/32 or C09K 15/326

Soil-conditioning materials or soil-stabilising materials (specially adapted for boreholes or wells C09K 8/00; fertilisers C05; consolidating by placing solidifying or pore-filling substances in the soil E02D 3/12)
Definition statement

This place covers:

Also covers mixtures of soil conditioning materials with fertilisers if the material is characterised by the soil conditioning or soil-stabilising activity

References
Limiting references

This place does not cover:

Specially adapted for boreholes or wells

Mixtures of soil conditioning materials with fertilisers characterised by the fertilising activity

Consolidating by placing solidifying or pore-filling substances in the soil

Informative references

Attention is drawn to the following places, which may be of interest for search:

Sports fields

Treatment of contaminated soils

Cement grouts

Fertilisers

Coating of dams

Protection of foundations

Securing of slopes

Special rules of classification

In C09K 17/02 - C09K 17/52 : Last Place Rule

Aluminium compounds, e.g. aluminium hydroxide
Definition statement

This place covers:

Also aluminates, zeolites, pozzolanic materials

applied in a physical form other than a solution or a grout, e.g. as platelets or granules
Definition statement

This place covers:

Also foams

Polyacrylates; Polymethacrylates
Definition statement

This place covers:

Also polyacrylamides

of natural origin, e.g. cellulosic materials
Definition statement

This place covers:

Also starch derivatives, sugars, proteins, biopolymers

Inorganic compounds mixed with organic active ingredients, e.g. accelerators
Definition statement

This place covers:

Also microorganisms as organic active ingredient

Mulches
Definition statement

This place covers:

also

- film-forming compositions

- cover layers , geotextile

References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Protective coverings for plants

Liquid crystal materials
Definition statement

This place covers:

Liquid crystal (LC) compounds (non-polymeric, as well as polymeric),

mixtures of liquid crystal compounds, and mixtures of liquid crystal compounds with additives that are NOT liquid crystal compounds (solvents, solid particles, macromolecular compounds, aligning agents, dopants, charge transfer agents, surfactants, pleochroic dyes).

Relationships with other classification places

Organic compounds C07

Organic macromolecular compounds C08

Optical elements, systems, or apparatus G02B

Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating, or modulating; Non-linear optics G02F 1/00

References
Limiting references

This place does not cover:

Polarising elements

The electronics of a liquid crystal display

Light-modulating devices

Informative references

Attention is drawn to the following places, which may be of interest for search:

Heterocyclic compounds containing five‑membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom

Copolymers in which the nature of only the monomers in minority is defined

Manufacture of films or sheets

Optical Filters

Holograms

Luminescent elements

Surface‑induced orientation of the liquid crystal molecules, e.g. by alignment layers

Recording or reproducing by optical means;Recording by modifying optical properties, (e.g. by using electromagnetic radiation)

Record Carriers

Special rules of classification

In the subgroups C09K 19/02 - C09K 19/603, in the absence of an indication to the contrary, materials are classified in the last appropriate place. In the case of Markush formulae, the inventive idea is classified. Further, an attempt is made to classify each exemplified embodiment.

The general philosophy could be summarized as follows:

LC compounds or the LC mixtures characterised in general by the optical, electrical or physical properties of the components are classified in the subgroups C09K 19/02 - C09K 19/0283. The two-dot subgroups C09K 19/0208 - C09K 19/0283 are non-hierarchical and each embodiment or example of a LC compound or mixture should be classified and may be placed in a different subgroup.

These subgroups cover LC compounds or the LC mixtures characterised in general by the chemical structure of the liquid crystal component, mainly the specific ring or rings or ring system(s) used, as well as the linking groups between the rings.

C09K 19/52 - C09K 19/603 These subgroups cover LC mixtures characterised in general by the chemical structure of the components, which are not liquid crystals, e.g. additives.

In short every document may classified

in one or more subgroups from C09K 19/02 - C09K 19/0283 and/or

in one or more subgroups from C09K 19/04 - C09K 19/50 and/or

in one or more subgroups from C09K 19/52 - C09K 19/603.

We place the LC embodiments in groups, where we expect to retrieve them accurately and efficiently during search. When in doubt, classify! What goes under a specific group is straightforward, since the title of the group is comprehensive.

Next to the ECLA Scheme (based on the ring(s) of the LC molecules), a non-hierarchical Indexing Code has been developed to cater for cases, where a specific unit, a linking group, an end group, the positioning of a substituent, or a special bonding is the characterising part of the chemical structure of the liquid crystal component, instead of the ring or rings that constitute the LC molecule.

That means that documents in various groups may get the same Indexing Code.

Figuratively speaking, the Indexing Code (C09K 19/04 - C09K 2019/0496 ) cuts vertically the EC-Scheme.

In other cases (C09K 19/06 to end) the Indexing Code gives

a more detailed view of the sequence of rings and linkers in a LC molecule or

a more detailed list of the compounding ingredients.

characterised by optical, electrical or physical properties of the components, in general
Special rules of classification

LC compounds or the LC mixtures characterised in general by the optical, electrical or physical properties of the components are classified in the subgroups C09K 19/02 - C09K 19/0283. The two-dot subgroups C09K 19/0208 - C09K 19/0283 are non-hierarchical and each embodiment or example of a LC compound or mixture should be classified and may be placed in a different subgroup.

characterised by the chemical structure of the liquid crystal components{, e.g. by a specific unit}
Definition statement

This place covers:

LC compounds or the LC mixtures characterised by the chemical structure of the liquid crystal components, that is by a specific unit - see the Indexing Code.

{the structure containing one or more specific, optionally substituted ring or ring systems}
Definition statement

This place covers:

LC compounds or the LC mixtures characterised in that the structure contains one or more specific, optionally substituted ring or ring systems - see the Indexing Code.

{Sugars (polysaccharides C09K 19/3819)}
Definition statement

This place covers:

Sugars.

References
Limiting references

This place does not cover:

Polysaccharides

Non-steroidal liquid crystal compounds
Definition statement

This place covers:

Non-steroidal liquid crystal compounds; e.g. linear compounds without any rings, as well as mainly containing ONE non-condensed ring.

Special rules of classification

Non-steroidal liquid crystal compounds; e.g. linear compounds like R1-COO-R2, R-O-CH=CH2, or R-COOH, as well as mainly containing ONE non-condensed ring like R-Cy-COOH, or R-(A-Z1)n-Cy-R2 with n=0-3.

containing at least two non-condensed rings
Definition statement

This place covers:

Liquid crystal compounds containing at least two non-condensed rings,

e.g. not naphthyl, fluorene and the like

If the rings are clearly defined,they are classified in lower subgroups C09K 19/10 - C09K 19/3098

containing at least two benzene rings
Definition statement

This place covers:

Liquid crystal compounds containing at least two benzene rings - see the Indexing Code.

Special rules of classification

A mixture of C09K 19/12 and/or C09K 19/126 and/or C09K 19/14 and/or C09K 19/16 and/or C09K 19/18 is classified in C09K 19/10. Here we stay in the common nod of the hierarchical tree, from which the five nods depend.

at least two benzene rings directly linked, e.g. biphenyls
Special rules of classification

In C09K 19/12 for example not only compounds such as Ph-Ph, Ph-Ph-Ph, Ph-Ph-Ph-Ph etc. are classified, but also mixtures of such compounds.

linked by a chain containing carbon and oxygen atoms as chain links, e.g. esters {or ethers}
Special rules of classification

A mixture of Ph-O-C2H4-Ph (C09K 19/20) and Ph-COO-Ph (C09K 19/2007) is classified in C09K 19/20. Here the common nod of the hierarchical tree, from which the two nods depend, is the first nod.

containing saturated or unsaturated non-aromatic rings, e.g. cyclohexane rings
Definition statement

This place covers:

Liquid crystal compounds containing saturated or unsaturated non-aromatic rings, e.g. cyclohexane, cyclohexene, cyclobutane rings - see the Indexing Code

Special rules of classification

A mixture of Cy-C2H4-Cy (C09K 19/3028) (II) and Cy-Ph-Ph (C09K 19/3003) (III) is classified in C09K 19/3001 (I). Here we stay in the common nod (I) of the hierarchical tree, from which the two nods (II) and (III) depend.

A mixture of C09K 19/3001 and/or C09K 19/3003 and/or C09K 19/3028 and/or C09K 19/3048 and/or C09K 19/3059 is classified in C09K 19/3001. Here we stay in the common nod of the hierarchical tree, from which the five nods depend.

{Compounds containing at least two rings in which the different rings are directly linked (covalent bond)}
Special rules of classification

A mixture of Cy-Ph-Cy (C09K 19/3003) and Cy-Ph-Ph (C09K 19/3003) is classified in C09K 19/3003. Here we stay in the same nod of the hierarchical tree.

containing condensed ring systems, i.e. fused, bridged or spiro ring systems
Definition statement

This place covers:

Liquid crystal compounds containing condensed ring systems, i.e. fused, bridged or spiro ring systems.

Here is a non limited list of fused, bridged or spiro ring systems classified under this group: anthracene, phenanthrene, fluorene, triphenylene, azulene, perylene, dibenzopyrene, twistane, bicyclopentane, hexabenzocoronene, resorcinarenes, propellane, truxene, carboranes, cubane,chrysene, decacyclene, calixarenes, triptycene, metacyclophanes, cyclotriveratrylene, cyclotetraveratrylene, trisbenzocyclononene, tetrabenzocyclododecatatraene, hexahelicene, octahelicene, fullerene.

containing at least one heterocyclic ring
Definition statement

This place covers:

Liquid crystal compounds containing at least one heterocyclic ring.

Special rules of classification

Liquid crystal compounds containing at least one heterocyclic ring, where the ring comprises oxygen, nitrogen, or sulfur or any combination of these three elements.

{Pyrazine}
References
Informative references

Attention is drawn to the following places, which may be of interest for search:

Also fused compounds, like quinoxaline.

Steroidal liquid crystal compounds
Definition statement

This place covers:

Steroidal liquid crystal compounds.

Special rules of classification

Liquid crystal cholesterol derivatives.

Polymers
Definition statement

This place covers:

Polymeric compounds with liquid crystalline properties.

References
Limiting references

This place does not cover:

Mechanical properties of the polymers appear

Special rules of classification

Here we classify polyesters and polyester derivatives such as polyamides, with mesogenic groups in the main chain.

containing elements other than carbon, hydrogen, halogen, oxygen, nitrogen or sulfur, e.g. silicon, metals
Definition statement

This place covers:

Liquid crystal compounds containing elements other than carbon, hydrogen, halogen, oxygen, nitrogen or sulfur, e.g. silicon, boron, phosphorus, metals.

Mixtures of liquid crystal compounds covered by two or more of the preceding groups C09K 19/06 - C09K 19/40
Definition statement

This place covers:

Mixtures of liquid crystal compounds.

Mixtures containing two or more liquid crystal compounds covered individually by the same group C09K 19/04 - C09K 19/408 are classified only in that group. In other words, in C09K 19/12 for example not only compounds such as Ph-Ph, Ph-Ph-Ph, Ph-Ph-Ph-Ph etc. are classified, but also mixtures of such compounds.

Different embodiments for LC mixtures may be classified in a different group. If liquid crystal components of the mixtures classified in groups from C09K 19/42 - C09K 19/50 are of importance as such, they should also be classified according to the compounds in groups from C09K 19/04 - C09K 19/408.

Special rules of classification

Here we classify mixtures of liquid crystal compounds containing compounds covered by two or more of the preceding groups C09K 19/06 through C09K 19/408 - compare the numbered sets 4 to 12 of the main subgroups. However, if all compounds of the mixture fall under the same head subgroup, the mixture is classified in that head subgroup. Some examples might clarify this:

• A mixture of Cy-Ph-Cy (C09K19/39A1) and Cy-Ph-Ph (C09K19/39A1) is classified in C09K19/39A1. Here we stay in the same nod of the hierarchical tree.

• A mixture of Cy-C2H4-Cy (C09K19/39A2) (II) and Cy-Ph-Ph (C09K19/39A1) (III) is classified in C09K19/39A (I). Here we stay in the common nod (I) of the hierarchical tree, from which the two nods (II) and (III) depend.

• A mixture of Ph-O-C2H4-Ph (C09K 19/20) and Ph-COO-Ph (C09K 19/2007) is classified in C09K 19/20. Here the common nod of the hierarchical tree, from which the two nods depend, is the first nod.

• A mixture of C09K 19/12 and/or C09K 19/126 and/or C09K 19/14 and/or C09K 19/16 and/or C09K 19/18 is classified in C09K 19/10. Here we stay in the common nod of the hierarchical tree, from which the five nods depend.

• A mixture of C09K 19/3001 and/or C09K 19/3003 and/or C09K 19/3028 and/or C09K 19/3048 and/or C09K 19/3059 is classified in C09K 19/3001. Here we stay in the common nod of the hierarchical tree, from which the five nods depend.

containing compounds with benzene rings directly linked
Special rules of classification

Here we classify mixtures of liquid crystal compounds containing compounds with benzene rings directly linked falling under C09K 19/12. Example Cy-C2H4-Cy and Ph-Ph.

containing esters
Special rules of classification

Here we classify mixtures of liquid crystal compounds containing ester compounds falling under C09K 19/2007 through C09K 19/2028, or under C09K 19/3068. Example Cy-OCF2-Cy and Ph-COO-Ph.

containing Schiff bases
Special rules of classification

Here we classify mixtures of liquid crystal compounds containing Schiff base compounds falling under C09K 19/22. Example Cy-OCH 2-Cy and Ph -CH=N-Ph.

containing steroidal liquid crystal compounds
Special rules of classification

Here we classify mixtures of liquid crystal compounds containing steroidal liquid crystal compounds falling under C09K 19/36.

characterised by components which are not liquid crystals, e.g. additives {with special physical aspect: solvents, solid particles}
Special rules of classification

These subgroups cover LC mixtures characterised in general by the chemical structure of the components, which are not liquid crystals, e.g. additives, solvents, organic or inorganic solid particles, macromolecular compounds, dopants.

Aligning agents
References
Limiting references

This place does not cover:

The alignment layers per se

Special rules of classification

Here we classify Aligning Agents used in admixture with LC materials to improve the aligning properties of the LC materials.

Fireproofing materials (for use in a particular application, see the relevant places, e.g. fireproofing of wood B27K, of polymers C08, of textiles D06M, of paper D21H; fireproof paints C09D 5/18)
Definition statement

This place covers:

Inorganic materials

Organic materials

Macromolecular materials

References
Limiting references

This place does not cover:

Fire-fighting

Fire-extinguishing compositions

Laminates

Refractory materials

Informative references

Attention is drawn to the following places, which may be of interest for search:

Fireproofing of wood

Fireproofing of polymers

C08

Fireproof paints

Fireproofing of textiles

Fireproofing of paper)

Protection of constructions against fire

Protection of pipes by means of non-inflammable material

Protection of cables

Special rules of classification

C09K relates to materials not provided elsewhere,

therefore

If the fire-proofing material is only claimed with regard to a particular application and if in said particular application field a class related to the chemical nature of the fireproofing material exists the document should only be classified in the application field

If no particular application of the fireproofing material is cited the document should only be classified in the appropriate C09K 21/00 group.

If the fireproofing material is claimed without particular uses the document should be classified in the appropriate C09K 21/00 group,

however

If particular applications are cited (e.g. in the description) the document should additionally be classified in the relevant application fields

and

if many different applications are cited the document should only be classified in the appropriate C09K 21/00 group.