Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 12/01/2025 has been entered.
This action is responsive to Applicant’s request for continued examination and amendment/remarks filed 12/01/2025.
Claims 1, 2, and 5-14 are currently pending.
Response to Amendment
The rejection of claim 6 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite is withdrawn in view of the above amendment. However, the claim as amended has a 112(d) issue. See below.
The rejection of claims 5 and 7 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite as previously set forth in the Office action mailed 07/30/2025 is maintained and has been revised below to reflect the changes in claim scope made by Applicant’s present claim amendments.
The rejection under 35 U.S.C. 103 as being unpatentable over Shankland et al. (US 2006/0043331 A1) as set forth in the previous Office action is maintained and has been revised below to reflect the changes in claim scope made by Applicant’s present claim amendments.
The rejection under 35 U.S.C. 103 as being unpatentable over Van Horn (US 2011/0288192 A1) is withdrawn in view of the above amendment. Van Horn teaches a blowing agent composition comprising about 25-75 wt.% HFO-1234ze and about 25-75 wt.% HFC-152a (see both the preferred range of 1234ze of there being “around 25 wt.% to around 75 wt.%” and the ratio of 1234ze with 152a of 1:3 to 3:1) optionally with about 1-3 wt.% carbon dioxide (CO2) (para. 0019) and shortly thereafter teaches that another embodiment of their invention is “the tetrafluoropropene in the blends described above is HFO-1234yf” (para. 0021). While Van Horn teaches/motivates an approximate composition of about/around 25-75 wt.% HFO-1234yf (2,3,3,3-tetrafluoropropene), about/around 25-75 wt.% HFC-152a (1,1-difluoroethane), and about 1-3 wt.% CO2 via para. 0019 & 0021, Van Horn fails to teach or suggest lowering the HFC-152a concentration to arrive at or approach the claimed range of 15-20 wt.% HFC-152a.
Priority
Acknowledgment is made of Applicant's claim for foreign priority based on applications filed in Korea on 08/16/2023 and 07/17/2024. It is noted, however, that Applicant has not filed a certified copy of either application (KR10-2023-0106988 or KR10-2024-0094667) as required by 37 CFR 1.55.
While the Office attempted to retrieve the foreign priority documents from the PTO/SB/38 filed 08/15/2024, Applicant was notified on 01/16/2025 that both retrieval requests failed. However, Applicant notes in the present response that Applicant has received no such notification. The Examiner double checked the application’s file wrapper and verified that there are two “PD.RETR.FAIL” documents with receipt dates of 01/16/2025 indicating the retrieval requests were unsuccessful dated 01/16/2025 in the file wrapper. The Examiner has attached copies of the two documents as appendixes to this Office action. The Examiner suggests Applicant review the URLs and contact information for further questions and assistance set forth in the retrieval request failure notices mailed 01/16/2025.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 5 and 7 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention.
Claim 5 recites “a ratio of the content of the 2,3,3,3-tetrafluoropropene to the content of the carbon dioxide based on the total weight of the mixed refrigerant composition ranges from 13 to 80.” This appears to have the meaning there is 13 to 80 times more 2,3,3,3-tetrafluoropropene than carbon dioxide. Claim 7 recites “a ratio of the content of the 2,3,3,3-tetrafluoropropene to the content of the 1,1-difluoroethane based on the total weight of the mixed refrigerant composition ranges from 3 to 6.” This appears to have the meaning there is 3 to 6 times more 2,3,3,3-tetrafluoropropene than 1,1-difluoroethane.
However, parent independent claim 1 has been amended narrowing the content of carbon dioxide from 1 to 10 wt.% to 1 to 5 wt.%, the content of 2,3,3,3-tetrafluoropropene from 65 to 95 wt.% to 75 to 85 wt.%, and the content of 1,1-difluoroethane from 15 to 23 wt.% to 15 to 20 wt.%. The requirement that there must be at least 15 wt.% 1,1-difluoroethane and at least 1 wt.% carbon dioxide (summing to 16 wt.%) means there can only be at the most 84 wt.% 2,3,3,3-tetrafluoropropene in the composition. While claim 1 is not indefinite itself, claim 1’s narrow concentrations has implications that render claims 5 and 7, dependent on claim 1, indefinite.
This amendment renders it unclear (rather than under a clear-cut 112(d) rationale) whether claims 5 and 7 each include all the limitations and/or further limit the limitations of claim 1.
Claim 5 is confusing because the required ranges of 75-85 wt.% (actually 75-84 wt.%, Id.) 2,3,3,3-tetrafluoropropene and 1-5 wt.% carbon dioxide do not permit there to be 2,3,3,3-tetrafluoropropene in an amount as broad as the end point amount of 13 times the amount of carbon dioxide. While the independent claim requires a minimum of 15 times more 2,3,3,3-tetrafluoropropene than carbon dioxide (75 wt.%:5 wt.%), the independent claim’s concentrations cannot have a concentration of 2,3,3,3-tetrafluoropropene that is 13 times more than carbon dioxide and it is unclear whether the limitations of claim 5 include all the limitations and/or further limit the limitations of claim 1.
Claim 7 is confusing because the required ranges of 75-85 wt.% (actually 75-84 wt.%, Id.) 2,3,3,3-tetrafluoropropene and 15-20 wt.% 1,1-difluoroethane do not permit there to be 2,3,3,3-tetrafluoropropene in an amount as broad as the end point amounts of 3 times the amount of 1,1-difluoroethane and 6 times the amount of 1,1-difluoroethane. While the independent claim requires a minimum of about 4 (3.75) times more 2,3,3,3-tetrafluoropropene than 1,1-difluoroethane (75 wt.%:20 wt.%) and a maximum of about 6 (5.6) times more 2,3,3,3-tetrafluoropropene than 1,1-difluoroethane (84 wt.%:15 wt.%), the independent claim’s concentrations cannot have a concentration of 2,3,3,3-tetrafluoropropene that ranges from 3 times to 6 times more than carbon dioxide and it is unclear whether the limitations of claim 7 include all the limitations and/or further limit the limitations of claim 1.
Appropriate correction/clarification is required.
For purposes of further examination (or else the claims might not be able to be fairly compared and weighed against prior art), claims 5 and 7 are interpreted as being limited only to ratios of components that are possible via the independent claim’s composition effectively comprising 1-5 wt.% carbon dioxide, 15-20 wt.% 1,1-difluoroethane, and 75-84 wt.% 2,3,3,3-tetrafluoropropene.
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 6 is rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Independent claim 1 recites a carbon dioxide concentration of 1-5 wt.% and a 1,1-difluoroethane concentration of 15-20 wt.%. This amounts to a broadest possible 1,1-difluoroethane/carbon dioxide content ratio of 3/1 to 20/1 (5/15 = 3; 20/1 = 20).
Claim 6 depends on claim 1 and recites “a ratio of the content of the 1,1-difluoroethane to the content of the carbon dioxide based on the total weight of the mixed refrigerant composition ranges from 3 to 20.” This has the meaning there is 3 to 20 times more 1,1-difluoroethane than carbon dioxide. However, the independent claim already has this exact content ratio and thus claim 6 fails to further limit parent claim 1.
Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Claim Interpretation
The independent claim has been amended on 12/01/2025 to recite the limitations “the 2,3,3,3-tetrafluoropropene is the major component, and the 1,1-difluoroethane is the second major component, based on the total weight of the mixed refrigerant composition” which is construed as meaning the composition contains the 2,3,3,3-tetrafluoropropene component in the greatest amount and the 1,1-difluoroethane component in the second greatest amount. However, this limitation is redundant and already included in the claim’s recited concentrations of the components. The independent claim recites the mixed refrigerant composition comprises “a content of the carbon dioxide ranges from 1 to 5% by weight … a content of the 2,3,3,3-tetrafluoropropene ranges from 75 to 85% by weight … a content of the 1,1-difluoroethane is 15 to 20% by weight” which already requires the 2,3,3,3-tetrafluoropropene component in the greatest amount and the 1,1-difluoroethane component in the second greatest amount.
As there is a minimum amount of 75 wt.% 2,3,3,3-tetrafluoropropene, there cannot be any compound in a greater amount than the 2,3,3,3-tetrafluoropropene meaning the 2,3,3,3-tetrafluoropropene is the major component.
As there is there is a minimum amount of 75 wt.% 2,3,3,3-tetrafluoropropene and a minimum amount of 15 wt.% 1,1-difluoroethane (having a minimum total amount of 90 wt.%), there cannot be any additional compound in a greater amount than the 1,1-difluoroethane’s 15+ wt.% meaning 1,1-difluoroethane is the second major component.
For purposes of further examination, prior art meeting/overlapping the recited “a content of the carbon dioxide ranges from 1 to 5% by weight … a content of the 2,3,3,3-tetrafluoropropene ranges from 75 to 85% by weight … a content of the 1,1-difluoroethane is 15 to 20% by weight” reads on the claimed redundant “the 2,3,3,3-tetrafluoropropene is the major component, and the 1,1-difluoroethane is the second major component, based on the total weight of the mixed refrigerant composition” limitation.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 2, and 4-14 are rejected under 35 U.S.C. 103 as being unpatentable over Shankland et al. (US 2006/0043331 A1).
As to claims 1, 2, and 4-13, Shankland et al. teach heat transfer fluid compositions for refrigeration comprising tetrafluoropropene and carbon dioxide (abstract). The compositions comprise about 60-99 wt.% of the tetrafluoropropene, preferably 2,3,3,3-tetrafluoropropene (HFO-1234yf) and about 1-40 wt.% of carbon dioxide (abstract and para. 0012), which overlap and encompass the claimed ranges of 75-85 wt.% 2,3,3,3-tetrafluoropropene and 1-5 wt.% carbon dioxide. Preferred compositions comprise about 70-95 wt.% 2,3,3,3-tetrafluoropropene (HFO-1234yf) and 5-30 wt.% carbon dioxide (para. 0012 & 0048), which overlaps and encompasses the claimed range of 75-85 wt.% 2,3,3,3-tetrafluoropropene and overlap/touches the claimed range of 1-5 wt.% carbon dioxide. Shankland et al. teaches additional HFCs such as 1,1-difluoroethane (HFC-152a) may be included in the compositions as a co-refrigerant with the tetrafluoropropene and carbon dioxide and present in a relative amount depending on the particular application for the composition and may be added to tailor the properties of the composition as needed (para. 0059-0074). Please especially see the list of additional compound species at para. 0030-0041 (each a single line) including 1,1-difluoroethane (HFC-152a) at para. 0036 and para. 0029 stating that the additional compound can include “one or more of the following” immediately preceding the list of additional compound species motivating provision of a single one of the listed species, i.e., HFC-152a as the only additional component beyond HFO-1234yf and CO2; the same is also substantially duplicated at para. 0059-0071 but with the list of additional species, including 1,1-difluoroethane (HFC-152a), termed as “co-refrigerants”.
While Shankland et al. fail to teach a single/exemplary composition under the meaning of anticipation to anticipate the claimed mixed refrigerant composition, at the time of the effective filing date it would have been obvious to a person of ordinary skill in the art to formulate and arrive within a composition overlapping the claimed concentrations of 2,3,3,3-tetrafluoropropene, 1,1-difluoroethane, and carbon dioxide as claimed by providing HFC-152a as a co-refrigerant additive in the HFO-1234yf/CO2 composition from the cited teachings of the reference in order to obtain a refrigerant/heat transfer composition with a reasonable expectation of success.
Such a formulated composition would have concentrations consisting of about 60-99 wt.% 2,3,3,3-tetrafluoropropene, about 1-40 wt.% carbon dioxide, and greater 0 wt.% and up to about 39 wt.% HFC-152a (calculated by subtracting the disclosed minimum amounts of required HFO-1234yf and CO2 components from 100 wt.%), which overlap and encompass the claimed ranges of 75-85 wt.% 2,3,3,3-tetrafluoropropene, 15-20 wt.% 1,1-difluoroethane, and 1-5 wt.% carbon dioxide. Similarly, such a formulated preferred composition would have concentrations consisting of about 70-95 wt.% HFO-1234yf, about 5-30 wt.% carbon dioxide, and greater than 0 wt.% and up to about 25 wt.% HFC-152a (calculated by subtracting the disclosed minimum amounts of required HFO-1234yf and CO2 components from 100 wt.%), which overlap and encompass the claimed ranges of 75-85 wt.% 2,3,3,3-tetrafluoropropene and 15-20 wt.% 1,1-difluoroethane and overlap/touches the claimed range of 1-5 wt.% carbon dioxide. Clearly, the sets of concentrations of 2,3,3,3-tetrafluoropropene, 1,1-difluoroethane, and carbon dioxide overlap the concentrations that are instantly claimed in claim 1. The additional limitations that the 2,3,3,3-tetrafluoropropene is the major component and the 1,1-difluoroethane is the second major component, both based on the total weight of the mixed refrigerant composition, are met for the same reason. Also, the sets of concentrations of 2,3,3,3-tetrafluoropropene, 1,1-difluoroethane, and carbon dioxide overlap the relative weight concentrations that are instantly claimed in claims 5-7. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976).
Regarding any remaining limitations among claims 1 and 8-13, while Shankland et al. fail to specifically teach the mixed refrigerant has certain properties within certain ranges (a certain boiling point, a certain critical temperature, a certain critical pressure, certain temperature glides at certain pressures, a certain latent heat, and a certain global warming potential) a person of ordinary skill in the art would expect and understand such properties would flow naturally from the cited teachings of the reference and above-presented rationale from the cited teachings of the reference since Shankland et al. teach substantially the same composition consisting of the same components (2,3,3,3-tetrafluoropropene, 1,1-difluoroethane, and carbon dioxide, Id.), in the same/overlapping ranges as claimed (about 60-99 wt.% preferably about 70-95 wt.% HFO-1234yf vs 65-95 wt.% as claimed, about 1-40 wt.% preferably 5-30 wt.% carbon dioxide vs 1-10 wt.% as claimed, and greater 0 wt.% and up to about 39 wt.% preferably greater than 0 wt.% and up to about 25 wt.% HFC-152a vs 15-23 wt.% as claimed, Id.). Also note the reference teaches the compositions have global warming potentials (GWP) of preferably less than 150 (para. 0051) but the reference encompasses GWPs well-within and overlapping the narrow range of <40 as claimed. GWP is well-known in the art as merely the weighted average of the GWPs of the respective compounds in a given composition. Note that Applicant has disclosed GWP values of the HFO-1234yf, HFC-152a, and carbon dioxide in the original specification as 4 or less, 150 or less, and 1, respectively. For example, a composition comprising 80 wt.% 2,3,3,3-tetrafluoropropene/HFO-1234yf, 15 wt.% 1,1-difluoroethane/HFC-152a, and 5 wt.% CO2 (all well-within the reference’s preferred ranges) has a GWP of about 21; also, a composition comprising 78 wt.% HFO-1234yf, 18 wt.% HFC-152a, and 4 wt.% carbon dioxide (all within the reference’s effective ranges) has a GWP of about 25. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). "Products of identical chemical composition can not have mutually exclusive properties." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. The fact that appellant has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious." Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
As to claim 14, Shankland et al. teach the compositions are suitable for use as refrigerants in heat pump systems (para. 0010 & 0073).
Response to Arguments
Applicant's arguments filed 12/01/2025 regarding Shankland et al. (US 2006/0043331 A1) have been fully considered but they are not persuasive.
Applicant argues Shankland et al. do not teach or suggest a refrigerant has contains the highest amount of 2,3,3,3-tetrafluoropropene (R-1234yf) and the second-highest amount of 1,1-difluoroethane (R-152a) as one of their preferred compositions at para. 0012 comprises 5-30 wt.% carbon dioxide and 70-95 wt.% R-1234yf which does not represent the compositional ratio of carbon dioxide and R-1234yf in a case where other refrigerants such as R-152a are also included. Applicant also argues a person of ordinary skill in the art would not add an additional component in a greater amount than the existing carbon dioxide or 2,3,3,3-tetrafluoropropene components in Shankland et al.’s composition.
In response, this argument is not persuasive because, as similarly explained in the interview held on 10/01/2025, Shankland et al.’s disclosed ranges of 2,3,3,3-tetrafluoropropene and carbon dioxide and motivation/suggestion to additionally include 1,1-difluoroethane indeed meet and read on a refrigerant composition having 2,3,3,3-tetrafluoropropene in the greatest amount and 1,1-difluoroethane in the second greatest amount as claimed.
First, regarding the claimed relative limitation of 2,3,3,3-tetrafluoropene, note that the broadest possible of tetrafluoropropene (preferably 2,3,3,3-tetrafluoropropene) in Shankland et al. is about 60-99 wt.% (abstract and para. 0012). As Shankland et al. require a minimum amount of 60 wt.% tetrafluoropropene (that is preferably 2,3,3,3-tetrafluoropropemne) there cannot be any compound in a greater amount than the tetrafluoropropene meaning Shankland et al. meet and encompass the claimed limitation that 2,3,3,3-tetrafluoropropene is the major component (present in the greatest/highest amount) as claimed.
Second, regarding the claimed relative limitation of 1,1-difluoroethane, Shankland et al. teach the compositions comprise about 60-99 wt.% of the tetrafluoropropene, preferably 2,3,3,3-tetrafluoropropene (HFO-1234yf) and about 1-40 wt.% of carbon dioxide (abstract and para. 0012). Shankland et al. further teaches additional HFCs such as 1,1-difluoroethane (HFC-152a) may be included in the compositions as a co-refrigerant with the tetrafluoropropene and carbon dioxide and present in a relative amount depending on the particular application for the composition and may be added to tailor the properties of the composition as needed (para. 0059-0074). Please especially see the list of additional compound species at para. 0030-0041 (each a single line) including 1,1-difluoroethane (HFC-152a) at para. 0036 and para. 0029 stating that the additional compound can include “one or more of the following” immediately preceding the list of additional compound species motivating provision of a single one of the listed species, i.e., HFC-152a as the only additional component beyond HFO-1234yf and CO2; the same is also substantially duplicated at para. 0059-0071 but with the list of additional species, including 1,1-difluoroethane (HFC-152a), termed as “co-refrigerants”. A simple cursory reading of the grammar “one or more”, sufficiently encompasses, permits, and motivates provision of a single “one” of the listed compounds (such as HFC-152a) alone. “one or more” means that provision of a single one of any of the listed compounds is included/permitted/motivated in Shankland et al.’s teachings. Provision of 1,1-difluoroethane as a single co-refrigerant additive or additional compound in the HFO-1234yf/CO2 composition as motivated by the cited teachings of the reference arrives a composition having concentrations consisting of about 60-99 wt.% 2,3,3,3-tetrafluoropropene, about 1-40 wt.% carbon dioxide, and greater 0 wt.% and up to about 39 wt.% HFC-152a (calculated by subtracting the disclosed minimum amounts of required HFO-1234yf and CO2 components from 100 wt.%), which overlap and encompass the claimed ranges of 75-85 wt.% 2,3,3,3-tetrafluoropropene, 15-20 wt.% 1,1-difluoroethane, and 1-5 wt.% carbon dioxide.
In a system (a composition in the present case) with three variable concentrations, a third variable (1,1-difluoroethane concentration) can be calculated if the first and second variables (2,3,3,3-tetrafluoropropene and carbon dioxide concentrations) are known. The 1,1-difluoroethane concentration can be calculated by subtracting the permitted concentrations of 2,3,3,3-tetrafluoropropene and carbon dioxide from 100%. The rejection of record made what is believed a reasonable and fair construction/calculation as to the concentration of the 1,1-difluoroethane (HFC-152a) co-refrigerant (when added as the sole co-refrigerant component as motivated by para. 0059, 0066, 0072, & 0074 of the reference) by subtracting the disclosed minimum amounts of required 2,3,3,3-tetrafluoropropene and carbon dioxide components from 100 wt.% so that the composition maintains the required concentrations ,3,3,3-tetrafluoropropene and carbon dioxide components elsewhere required in the reference at the abstract and para. 0012.
As the cited teachings amount to a composition having concentrations consisting of about 60-99 wt.% 2,3,3,3-tetrafluoropropene, about 1-40 wt.% carbon dioxide, and greater 0 wt.% and up to about 39 wt.% HFC-152a, Shankland et al. meet and encompass the claimed limitation that 1,1-difluoroethane is the second major component (present in the second greatest/highest amount) as claimed.
Applicant further argues Shankland et al. lists other additional compositions that can be added to the mixed refrigerant where 1,1-difluoroethane (R-152a) is merely one component among many others listed and Shankland et al. does not disclose the addition of R-152a alone. Applicant further argues Shankland et al. only discloses R-152a being added in the form of R-500 which is a blend of CFC-12 and R-152a in a 73.8:26.2 at para. 0043 meaning that a person of ordinary skill in the art would not add R-152a but would instead add it as a mixture with a CFC-series refrigerant.
In response, this argument is not persuasive because Applicant’s citation/argument to para. 0043 allegedly requiring a blend of CFC-12 and R-152a when R-152a misconstrues the reference. Para. 0043 clearly states Shankland et al.’s (tetrafluoropropene- and carbon dioxide-containing) compositions are useful as replacements for combinations of HFCs and CFCs (such as the combinations of CFC-12 and 1,1-difluorethane (HFC-152a), e.g., R-500) in refrigerant, aerosol, and other applications. This describes the intended use or purpose of Shankland et al.’s composition and does not require Shankland et al.’s composition to require CFC-12 when containing HFC-152a as alleged. In the refrigerant, aerosol, and related halocarbon composition arts, “replacement” means the inventive/newer composition literally replaces a prior, existing composition. Here, Shankland et al. is describing their inventive tetrafluoropropene- and carbon dioxide-containing compositions are suitable for replacing various prior compositions such as R-500 (which is a blend CFC-12 and HFC-152). See also para. 0056 of Shankland et al. further teaching their composition are used as a replacement for existing refrigerants. A person of ordinary skill in the art would not provide Shankland et al.’s 1,1-difluoroethane as a mixture with a chlorofluorocarbon (CFC) such as CFC-12 as alleged by Applicant because the reference neither states nor suggests such.
Furthermore, regarding Applicant’s concern that Shankland et al. allegedly does not disclose the addition of 1,1-difluoroethane (R-152a) alone, as described in the Final Office action mailed 07/30/2025, Shankland et al. clearly teach the additional compound/co-refrigerant may be “one or more of the following” where only twelve (12) particular compounds are listed, one of which being the claimed 1,1-difluoroethane (HFC-152a) (see para. 0029-0041 and 0059-0071 of the reference), that, even from a simple cursory reading of the grammar “one or more”, sufficiently encompasses, permits, and motivates provision of a single “one” of the listed compounds (such as HFC-152a) alone. “one or more” means that provision of a single one of any of the listed compounds is included/permitted/motivated in Shankland et al.’s teachings. While “one or more” alternative includes/permits/motivates a mixture of the stated compounds, a mixture of co-refrigerants is not necessarily required as alleged by Applicant; “one or more” means that mixture embodiments (“more”) are in the alternative (“or”) from single compound embodiments (“one”). In any event, the reference’s teachings/suggestions of providing alternative co-refrigerants other than HFC-152a, optionally in a mixture, does not constitute a teaching away because the disclosure does not criticize, discredit, or otherwise discourage the solution claimed.
Applicant further argues the claimed carbon dioxide concentration of 1-5 wt.% is critical and affords the claimed composition unexpected results. This argument regarding criticality and unexpected results is exclusively based on the contents of the contents of a 132 Declaration by Ji Seong Noh filed on 12/01/2025 and will be fully addressed separately in the next section, below.
Declaration of Ji Seong Noh
Page 1 at ¶ 1 to 3 of the declaration provide a summary of the declarant’s background and understanding of the rejection of record over Shankland et al. Pages 1 to 5 at ¶ 4 to 5 of the declaration provides new data (Comparative Examples 7 to 10) and appends this data to the specification’s comparative showing of record (Examples 1 to 21 and Comparative Examples 1 to 6), presenting all the cumulative data of record in Tables A & B. Pages 5 to 6 at ¶ 6 to 10 of the declaration are a discussion of the comparative data of record to allege the claimed carbon dioxide concentration of 1-5 wt.% is critical and affords the claimed composition unexpected results. The remainder of pages 6 and 7 at ¶ 11 of the declaration is a concluding statement and the declarant’s signature and date.
After careful and full consideration of its contents, the declaration filed 12/01/2025 is insufficient to overcome the 103 rejection of record over Shankland et al. (US 2006/0043331 A1).
The declaration alleges the claimed carbon dioxide concentration of 1-5 wt.% is critical and affords the claimed composition unexpected results because: 1) the Examples’ exhibit a Max Pressure of All Modes of less than 145%, a Cooling Mode Cd-Glide of 10.2°C or less, and a maximum temperature glide of approximately 10°C which suggests the compositions are capable of being used as a high drop-in/replacement refrigerant for existing systems/refrigerants, 2) the Comparative Examples including 7 wt.% or more carbon dioxide exhibit a Max Pressure of All Modes of greater than 157% a Cooling Mode Cd-Glide of greater than 12.4°C, an increase in volumetric capacity, and an increase in compressor outlet pressure which indicates these compositions are not suitable as a drop-in/replacement refrigerant for existing systems, and 3) some of the Comparative Examples have high temperature glides that might lead to detrimental supercooling or temperature variation indicating these compositions are insufficient as commercial candidates. ¶ 6 to 8 and 10. The declaration also alleges compositions with a high amount of 1,1-difluoroethane have an undesirable worst case of fractionation for flammability property that indicate a high likelihood that the composition will be merely have an A2 safety classification, failing to meet the A2L safety classification required for automotive applications. ¶ 9.
In response, these arguments and data are not persuasive to establish the results are unexpected, significant, and/or critical because the claims are not commensurate in scope with the probative value of data in the examples. The independent claim requires a composition comprising 1-5 wt.% carbon dioxide, 75-85 wt.% 2,3,3,3-tetrafluoropropene, and 15-20 wt.% 1,1-difluoroethane. However, the Table A in the declaration shows concentrations outside the claimed ranges have substantially the same properties as those inside the claimed ranges at the same relative wt.% of carbon dioxide. Note that, among the inventive examples, only Examples 3, 4, 7, 8, 11, 12, 15, 16, 19, and 20 are within the scope of the claims and Examples 1, 2, 5, 6, 9, 10, 13, 14, 17, 18, and 21 are all outside the scope of the claims.
For example, Example 2 has a composition of 1 wt.% carbon dioxide, 89 wt.% 2,3,3,3-tetrafluoropropene, and 10 wt.% 1,1-difluoroethane and is outside the scope of the claims while Example 3 has a composition of 1 wt.% carbon dioxide, 84 wt.% 2,3,3,3-tetrafluoropropene, and 15 wt.% 1,1-difluoroethane and is inside the scope of claims. However, both Examples have nearly the same boiling point (-35.338°C vs -35.082°C), critical temperature (96.603°C vs 97.119°C), critical pressure (36.873 bar vs 37.431 bar), max pressure (both 109%), cd-glide (2.3°C vs 2.2°C), and flammability class (both A2L). Similar rationale exists over the other related inventive examples.
The Table demonstrates there is an infinitesimal difference in properties for the carbon dioxide/2,3,3,3-tetrafluoropropene/1,1-difluoroethane blends whether they are inside out outside the claimed ranges of 2,3,3,3-tetrafluoropropene and/or 1,1-difluoroethane concentrations. Also note that the inventive examples comprising 1-5 wt.% carbon dioxide inside the claims and the comparative examples comprising 7 wt.% carbon dioxide outside the claims all obtain the same flammability classification of A2L. Obtaining results alleged as unexpected outside the claimed range(s) is not indicative of unexpected results.
Also, the comparative data of record demonstrates that for each 1 wt.% of carbon dioxide added the Max Pressure property generally increases by 8% to 9% in a near-linear relationship. Per Table A, 1 wt.% CO2 has a Max Pressure of 109%, 2 wt.% CO2 has a Max Pressure of 118% (an increase of 9% from the prior), 3 wt.% CO2 has a Max Pressure of 126% (an increase of 8% from the prior), 4 wt.% CO2 has a Max Pressure of 134% to 135% (an increase of 8% to 9% from the prior), 5 wt.% CO2 has a Max Pressure of 141% to 144% (an increase of about 8% to 9% from the prior), and 7 wt.% CO2 has a Max Pressure of 157% to 160% (an increase of about 8% per wt.% of carbon from the prior). Other rationale to general increases/decreases exist (e.g., boiling point generally decreases as carbon dioxide increases, critical pressure generally slightly increases as carbon dioxide increases, and cd-glide generally increases as carbon dioxide increases). These relationships of some properties increase while others decrease or some properties improve at the at the expense of others at the varying concentrations merely demonstrates trade-offs between the properties rather than amounting to a true showing of unexpected results.
It is also noted that the newly presented data of the comparative showing compares the claimed carbon dioxide concentration range of 1-5 wt.% to compositions with 7 wt.% carbon dioxide. Performance of 7 wt.%-based compositions is insufficient to demonstrate criticality of a 1-5 wt.% carbon dioxide range. Comparative examples with 6 wt.% carbon dioxide should be compared to demonstrate criticality of a 1-5 wt.% carbon dioxide range.
The evidence relied upon should establish "that the differences in results are in fact unexpected and unobvious and of both statistical and practical significance." Ex parte Gelles, 22 USPQ2d 1318, 1319 (Bd. Pat. App. & Inter. 1992). To establish unexpected results over a claimed range, applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range. In re Hill, 284 F.2d 955, 128 USPQ 197 (CCPA 1960).
The comparative data is record is also of little probative value in the determining patentability of claims since they do not involve a comparison of Applicant’s invention with the closest applied prior art, Shankland et al. What comparative example(s) are representative of Shankland et al.’s compositions? Shankland et al. teach a base binary composition of carbon dioxide and 2,3,3,3-tetrafluoropropene (abstract & para. 0012) that can contain additives such as 1,1-difluoroethane. Shankland et al.’s working examples have exemplary binary blends of, in carbon dioxide wt.% to 2,3,3,3-tetrafluoropropene wt.%, 1/99, 5/95, 10/90, 20/80, and 35/65 (Example 2, Fig. 7, & Fig. 8). None of the closest applied prior art reference’s examples have been compared. An affidavit or declaration under 37 CFR 1.132 must compare the claimed subject matter with the closest prior art to be effective to rebut a prima facie case of obviousness. See In re Burckel, 592 F.2d 1175, 201 USPQ 67 (CCPA 1979), In re De Blawe, 222 USPQ 191 (FED. Cir. 1984), and In re Fenn, 208 USPQ 470 (CCPA 1981).
The comparative showing is also deficient in another manner. To establish the existence of unexpected results, Applicant must establish through the introduction of evidence both that (1) there is actually a difference between the results obtained through the claimed invention and those of closest prior art and (2) the observed difference would have been unexpected by a person having ordinary skill in the art. In re Freeman, 474 F.2d 1318, 1324 (CCPA 1973). In this case, Applicant has not provided evidence that, as of the application's effective filing date, a person having ordinary skill in the art would have considered the results presented in the data to have been unexpected or surprising. The arguments do not cite evidence regarding the unexpected nature of the observed differences. The positions in the declaration seem to be underpinned by the belief that because some results are better, i.e., superior or improved, compared to others then the results are unexpected. However, because superiority alone is not sufficient to show that the result is unexpected, Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 1371 (Fed. Cir. 2007) (“[A]ny superior property must be unexpected to be considered as evidence of non-obviousness.”), Applicant has not provided evidence of the unexpected nature of the observed results.
Any of Applicant’s arguments set forth in the present remarks that are based on the declaration are also not persuasive for the same reasons that the declaration is insufficient to withdraw the 103 rejection.
In view of the foregoing, the rejection is maintained for the reasons of record.
The remaining references listed on Forms 892 and 1449 have been reviewed by the Examiner and are considered to be cumulative to or less material than the prior art references relied upon or described above.
Correspondence
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/MATTHEW R DIAZ/Primary Examiner, Art Unit 1761
/M.R.D./
February 20, 2026