F25J LIQUEFACTION, SOLIDIFICATION, OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT
Introduced: September 1968
Classification Context
- Section:
- MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- Class:
- REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION OR SOLIDIFICATION OF GASES
- Subclass:
- LIQUEFACTION, SOLIDIFICATION, OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT
Description
F25J covers apparatus and processes for liquefying, solidifying, or separating gases and gaseous mixtures through combined application of pressure and low-temperature treatment. This subclass encompasses cryogenic separation technologies including rectification columns, heat exchangers, expansion devices, and complete liquefaction plants for industrial gases such as nitrogen, oxygen, argon, and natural gas. The classification includes both the refrigeration systems and mechanical equipment necessary to achieve the required pressure-cold conditions, as well as methods for air separation and purification of gas streams.
Filing statistics
IPC subclass F25J recorded 16,536 patent applications worldwide between 2013 and 2023. Annual filings grew from 1,165 in 2013 to 1,617 in 2023 (+39%), peaking at 1,899 applications in 2022. The most active applicants in class F25 are HAIER SMART HOME (13,215 applications), LG ELECTRONICS (8,561 applications) and MIDEA (7,315 applications).
Source: EPO PATSTAT, worldwide filings
In class comparison
F25J ranks 4th of 4 subclasses with filings in F25, with 16,536 applications between 2013 and 2023, 4.2% of the class. Annual filings grew 39% from 2013 to 2023, below the class as a whole (+117%).
| Rank | Subclass | Title | Applications | Share |
|---|---|---|---|---|
| 1 | F25D, Refrigerators; Cold Rooms; Ice-Boxes; Cooling or Freezing Apparatus Not Otherwise Provided for | Refrigerators; Cold Rooms; Ice-Boxes; Cooling or Freezing Apparatus Not Otherwise Provided for | 179,372 | 45.8% |
| 2 | F25B, Refrigeration Machines, Plants or Systems; Combined Heating and Refrigeration Systems; Heat Pump Systems | Refrigeration Machines, Plants or Systems; Combined Heating and Refrigeration Systems; Heat Pump Systems | 178,629 | 45.6% |
| 3 | F25C, Producing, Working or Handling Ice | Producing, Working or Handling Ice | 16,883 | 4.3% |
| 4 | F25J | Liquefaction, Solidification, or Separation of Gases or Gaseous Mixtures by Pressure and Cold Treatment | 16,536 | 4.2% |
Source: EPO PATSTAT, worldwide filings
Related Keywords
3 direct subcodes
Child Classifications
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- F25J 1/00 Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J 3/00 Processes or apparatus for separating the constituents of gaseous mixtures involving the use of liquefaction or solidification
- F25J 5/00 Arrangements of cold-exchangers or cold-accumulators in separation or liquefaction plants
Top Applicants
Top 10 applicants by patent filingsfor class F25, 2013–2023, worldwide · Source: EPO PATSTAT
- HAIER SMART HOME 13,215
- LG ELECTRONICS KR 8,561
- MIDEA 7,315
- GREE ELECTRIC APPLIANCES 6,041
- HEFEI MIDEA REFRIGERATOR COMPANY 5,211
- MITSUBISHI ELECTRIC CORPORATION JP 4,905
- HEFEI HUALING COMPANY 4,633
- BSH (BOSCH UND SIEMENS HAUSGERAETE) DE 3,697
- QINGDAO HAIER INTELLIGENT TECHNOLOGY RESEARCH ANDDEVELOPMENT COMPANY 3,376
- HAIER SMART HOME CN 3,265