HOME > News Topics : Patent Landscape about HFO Refrigerants and Hydrocarbon Refrigerants Used for Refrigerators and Air Conditioners

Patent Landscape about HFO Refrigerants and Hydrocarbon Refrigerants Used for Refrigerators and Air Conditioners

2014/11/17


Global warming and next generation refrigerants

Based on adoption of the Montreal Protocol and the Kyoto Protocol, in the fields of refrigerators and air conditioners, attempts to develop refrigerants having little influence on the global environment such as ozonosphere disruption and global warming has been made.
Refrigerants used for air conditioners and refrigerators have been shifted from specific chlorofluorocarbon (CFC) refrigerants such as R22 to alternative chlorofluorocarbon refrigerants such as R410A so far. Although hydrofluorocarbons (HFCs) used for refrigerants as alternative CFCs have 0 ozonosphere disruption potential, HFCs still have high global warming potential (GWP). Accordingly, the further development of next generation refrigerants having 0 ozonosphere disruption potential and small GWP is attracting attention.
As the candidates for the next generation refrigerants, natural refrigerants such as carbon dioxide, ammonia and hydrocarbons, and low GWP fluorine-containing refrigerants are conceivable. As specific required conditions for the next generation refrigerants, the safety such as non-toxicity and a low risk of flammability, and the environmental friendliness such as 0 ozonosphere disruption potential and extremely low global warming potential are required. At the same time, the excellent LCCP (Life Cycle Climate Performance), the performance during the cooling operation equivalent to that of the conventional refrigerants, and the manufacturability at a reasonable cost are also required. (1)
As one of the candidates for the next generation refrigerants, the refrigerant R32 (difluoroethane) is conceivable. The R32 is one of the HFCs, and one of the constituents of mixed refrigerants R410A and R407C, which are now widely used as refrigerants for air conditioners. The GWP of the R32 as a single element is 675, which is one third of that of the R410A. Although it has a risk of slight flammability, because the operating efficiency is relatively good, and because it is also excellent in safety and economic aspects, air conditioners using the R32 alone as a working refrigerant have already been commercialized.
In addition, it is known that hydrofluoroolefins (HFOs) also have low GWP, and the HFOs are attracting attention as candidates for the next generation refrigerants. Among them, R1234yf (2,3,3,3-tetrafluoro-1-propene) has been developed by U.S. Du Pont and Honeywell as an alternative refrigerant for R134a currently used for automobile air conditioners. In the EU, the Mobile Air Conditioning Directive (MAC), which requires to gradually replace the R134a, the current mainstream of refrigerants for automobile air conditioners, with refrigerants having GWP of 150 or less, has already took effect in 2006, and the R1234yf is a refrigerant developed to deal with the Directive.(2),(3)
The HFO refrigerants have a risk of slight flammability, and problems such as increase in flammability under a high humidity condition and high pressure loss are pointed out. However, because the HFO refrigerants are non-toxic and have low GWP (for the R1234yf, GWP=4), in accordance with the EU Directive, introduction of the HFO refrigerants to automobile air conditioners is promoted. Although there has been no practical example of utilization of the HFO refrigerant as a refrigerant for a stationary air conditioner so far, there is a possibility that the HFO refrigerant is applied as a refrigerant for air conditioners other than the automobile air conditioner in the future.
In addition to the above, hydrocarbon refrigerants (such as isobutane and propane) are also considered to be candidates for alternative of conventional refrigerants. Japanese companies have actively performed research and development for hydrocarbon refrigerants, and various products such as a refrigerator using isobutene as a refrigerant have already been put into practice.(4) On the other hand, the hydrocarbons are high combustible substances, and has high risks of explosion and fire. Therefore, when utilizing the hydrocarbons as a refrigerant for an air conditioner, ensuring the safety is a problem to be solved.

Patent Analysis

Based on the technical backgrounds described above, in this report, we analyzed patent application trends concerning the hydrofluoroolefin (HFO) refrigerants and the hydrocarbon refrigerants which may be used as the next generation refrigerants for an air conditioner in the future.
Patents and patents applications related to the HFO are patents and patents applications whose claims are directed to the manufacturing of the hydrofluoroolefin or the use of the hydrofluoroolefin as a refrigerant, mixed refrigerants of the hydrofluoroolefin and other substances, the hydrofluoroolefin constituting refrigerating machine oil in combination with lubricating oil, and refrigerators or air conditioners (including refrigerating or air conditioning system components such as a compressor, a condenser and an evaporator) using the hydrofluoroolefin (including mixed refrigerants) as a refrigerant.
Similarly, extraction objects as patents and patent applications related to the hydrocarbon are patents and patents applications whose claims are directed to the refrigerants using the hydrocarbon alone, mixed refrigerants of the hydrocarbon and other substances, the hydrocarbon refrigerant constituting refrigerating machine oil in combination with lubricating oil, and refrigerators or air conditioners (including refrigerating or air conditioning system components such as a compressor, a condenser and an evaporator) using the hydrocarbon refrigerant (including mixed refrigerants) as a refrigerant. It should be noted that the technology for extracting the hydrocarbon from energy source materials such as petroleum and natural gas were not extracted.

[HFO refrigerant]
(Japanese Patent Analysis)
810 Japanese patent publications are analyzed as related to the subject technology. In the analysis, the patents are valid and the patent applications that are pending in October 2014 are analyzed.
Among 810 patent publications, 619 publications are related to HFO refrigerants and 284 publications are related to hydrocarbon refrigerants. (Database used: Shareresearch)

Among patents and patent applications which are analysis objects, 619 patents and patent applications were extracted as patents and patent applications related to the HFO, and the patent application technology trends are summarized as follows. The figure shown below illustrates changes in the number of patents and patent applications related to the HFO.

The patents and patent applications related to the HFO can substantially be confirmed in 2005 and later, and more than 100 patent applications have been filed since 2009. The number of patent applications has been increasing. It should be noted that with regard to the patent applications in and after 2012, there may be unpublished patent applications at the time of this analysis, and such unpublished patent applications are not included in the figure.

Next, patents and patents applications (pending) related to the HFO are classified into the following four classifications based on the characteristic of the invention: (1) related to the refrigerant itself; (2) related to the refrigerating machine oil; (3) related to the operating condition or handling of the refrigerant; and (4) related to the apparatus using the refrigerant. The figure shown below illustrates changes in the number of patent applications for each classification.

Since 2005, patent applications regarding the HFO refrigerant itself have been increasing. Further, since 2008, it is revealed that patent applications have been filed not only for inventions regarding the refrigerant itself but also for inventions in which the HFO refrigerant is applied to apparatuses such as an air conditioner and a refrigerator, and inventions regarding the operating condition. In this regard, it is presumed that applications have been filed for inventions regarding specific apparatus improvements aiming at commercialization of the HFO refrigerant and inventions related to apparatuses taking the HFO into consideration as an example of the used refrigerants.
Applicant rankings are shown below for four classifications of patents and patent applications related to the HFO.
With regard to inventions regarding the HFO refrigerant itself, Honeywell International Inc. who has played a major role in the development of R1234yf takes the first place. It is revealed that Japanese domestic air conditioner manufacturers have also actively filed patent applications for inventions regarding the apparatus.

(Refrigerant)
Rank Applicant/Owner Number
1 Honeywell International Inc. 129
2 ARKEMA 60
3 Central Glass Co., Ltd. 40
4 Mexichem Amanco Holding 36
5 E. I. DuPont 35

(Refrigerating machine oil)
Rank Applicant/Owner Number
1 JX Nippon Oil & Energy Corporation 32
2 Idemitsu Kosan Co., Ltd. 16
3 ARKEMA 3
4 Sanyo Electric Co., Ltd. 3
5 Idemitsu Kosan Co., Ltd.; Toyota Industries Corporation; and Denso Corporation (Joint application) 2

(Operating Condition)
Rank Applicant/Owner Number
1 ARKEMA 6
2 Mitsubishi Electric Corporation 4
3 Honeywell International Inc. 4
4 E. I. DuPont 2
5 Idemitsu Kosan Co., Ltd.; Denso Corporation; and Toyota Industries Corporation (Joint application) 1
5 Asahi Glass Co., Ltd. 1
(Apparatus)
Rank Applicant/Owner Number
1 Mitsubishi Electric Corporation 58
2 Panasonic Corporation 43
3 Sanden Corporation 11
4 Denso Corporation 6
5 ARKEMA 5

(Oversea Patent Analysis)
1026 patent families that are related to the subject technology and that have US,EP,CN,IN family members as filing countries.
Among 1026 patent families, 780 families are related to HFO refrigerants and 395 families are related to hydrocarbon refrigerants. (Database used: PatBase)
Number of patent families related to HFO refrigerants are shown in the following figures.




[Hydrocarbon Refrigerant]
(Japanese Patent Analysis)
Among 830 Japanese publications, 284 patent publications are related to hydrocarbon refrigerant. The patent application technology trends are summarized as follows.
The figure shown below illustrates changes in the number of patents and patent applications related to the hydrocarbon refrigerant. With regard to the changes in the number of patent applications for the hydrocarbon refrigerant, we could not recognize any significant increase and a period in which an application peak exists.
Since the objects of this analysis are patents in force and pending patent applications, if we take lapsed patents and patent applications into consideration, it is considered that the increasing trend in the changes of the number of patent applications is much smaller.


Patents and patents applications (pending) related to the hydrocarbon refrigerant are classified into the following four classifications based on the characteristic of the invention: (1) related to the refrigerant itself; (2) related to the refrigerating machine oil; (3) related to the operating condition or handling of the refrigerant; and (4) related to the apparatus using the refrigerant. The figure shown below illustrates changes in the number of patent applications for each classification.

It is revealed that patent applications for apparatuses using hydrocarbon refrigerants have been continuously filed since the latter half of the 1990s. With regard to the refrigerating machine oil, a remarkable peak was confirmed in 2007.
Next, applicant rankings are shown below for four classifications of patents and patent applications related to the hydrocarbon refrigerants.

(Refrigerant)
Rank Applicant/Owner Number
1 JX Nippon Oil & Energy Corporation 23
2 E. I. DuPont 11
3 ARKEMA 7
4 Central Glass Co., Ltd. 6
5 Mexichem Amanco Holding 4
5 Honeywell International Inc. 4

(Refrigerating machine oil)
Rank Applicant/Owner Number
1 JX Nippon Oil & Energy Corporation 30
2 Idemitsu Kosan Co., Ltd. 22
3 Japan Energy Corporation 5
4 Asahi Glass Co., Ltd. 2
4 Whirlpool S.A. 2

(Operating Condition)
Rank Applicant/Owner Number
1 ARKEMA 2
1 E. I. DuPont 2
3 ExxonMobil Upstream Research Company 1
3 Asahi Glass Co., Ltd. 1
3 Mitsubishi Electric Corporation 1

(Apparatus)
Rank Applicant/Owner Number
1 Panasonic Corporation 41
2 Mitsubishi Electric Corporation 37
3 Toshiba Carrier Corporation 9
3 Hitachi Appliances, Inc. 9
3 Denso Corporation 9

(Oversea Patent Analysis)
Among 1026 patent families, 395 families are related to hydrocarbon refrigerants. (Database used: PatBase) Number of patent families related to hydrocarbon refrigerants are shown in the following figures.




(References)
(1) The Japan Refrigeration and Air Conditioning Industry Association (JRAIA), Approaches Towards Global Warming Prevention and Next Generation Refrigerants by JRAIA, 2011
(2) Found in the website of Du Pont at:
http://www2.dupont.com/hfo1234yf/en_US/
(3) Found in the website of Honeywell Japan at;
http://honeywell.com/sites/JP/News/Pages/JPJRCHFO-1234yf.aspx
(4) Reports on Patent Application Technology Trends in 2007, Heating and Cooling Using Natural Refrigerant (Abridged edition)

▲ Top of the page