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 .
This action is responsive to Applicant’s amendment/remarks filed 01/08/2026.
Claims 1 and 3-6 are currently pending.
Information Disclosure Statement
The IDS statement filed 09/03/2025 has been considered. An initialed copy accompanies this action.
It is noted that, for all three of the foreign patent references in a foreign language, Applicant has merely provided translations of the abstracts of the foreign patent references. While the references have been considered to the best of the Examiner’s ability, the contents of the references/pages in foreign languages have not been considered. Only the abstracts have been considered. Applicant is reminded 37 CFR 1.98(a)(3) requires a concise explanation of the relevance, as it is presently understood by the individual designated in § 1.56(c) most knowledgeable about the content of the information, of each publication that is not in the English language.
Response to Amendment
The rejection of claims 3 and 4 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite is withdrawn in view of the above amendment. The claims have been amended to recite clear and definite concentration ranges.
The Office notes Applicant's remarks to the 112(b) rejection pertain to an alleged 112(b) rejection over the term "about". However, note that the 112(b) rejection presented in the prior Office action was over unclear format of molar ratio ranges ("xx to xx to xx to xx") that permitted more than one reasonable interpretation of the ranges, not over the term "about". See pages 2 to 3 of the Non-Final Office action mailed 07/08/2025.
As implied on page 4 of the Non-Final Office action mailed 07/08/2025, the Office interprets the term "about" as meaning "approximately". In the context of the term as it is used in the specification and claims of the instant application, "about" is a clear and definite broad term, not an indefinite term. Breadth is not indefiniteness.
The rejection of claims 1, 3, and 4 under 35 U.S.C. 102(a)(1,2) as being anticipated by Flaherty et al. (US 7,186,869 B2) is withdrawn in view of the above amendment. The claims have been amended to a require the composition comprise 1-99 mol% 1-chloro-1,2-difluoroethylene and 1-99 mol% 2,3,3,3-tetrafluoropropene. Flaherty et al. teach a doped R-134a mixture comprising mostly R-134a (1,1,1,2-tetrafluoroethane) and several halocarbon impurity compounds, including 6 ppm c-A1122a (cis-1-chloro-1,2-difluoroethylene), 1 ppm t-A1122a (trans-1-chloro-1,2-difluoroethylene), and 14 ppm A1234yf (1,1,1,2-tetrafluoroprop-2-ene which is structurally the same as the claimed 2,3,3,3-tetrafluoropropene i.e. 2,3,3,3-tetrafluoroprop-1-ene) (see Example 1 & Table 1 in col. 5; see also the key for the abbreviations of these compounds in col. 1 especially lines 23-24 & 53-55). The disclosed 1 ppm 1-chloro-1,2-difluoroethylene and 14 ppm 2,3,3,3-tetrafluoropropene in a composition with 27 ppm of other impurities and the remainder 1,1,1,2-tetrafluoroethane is significantly below and outside each of the claimed 1-99 mol% 1-chloro-1,2-difluoroethylene and 1-99 mol% 2,3,3,3-tetrafluoropropene ranges.
The rejection of claims 1, 3, and 4 under 35 U.S.C. 102(a)(1,2) as being anticipated by Merkel et al. (US 8,975,454 B2) is withdrawn in view of the above amendment. The claims have been amended to a require the composition comprise 1-99 mol% 1-chloro-1,2-difluoroethylene and 1-99 mol% 2,3,3,3-tetrafluoropropene. Merkel et al. teach a purified HFO-1234yf (2,3,3,3-tetrafluoropropene) product comprising 99.9671 wt.% HFO-1234yf and 3 ppm R-1122a (i.e., 1-chloro-1,2-difluoroethylene) as an impurity among other impurities (see Table 2 in col. 15). The disclosed 99.9671 wt.% HFO-1234yf and 3 ppm R-1122a in a composition with about 324 ppm of other impurities is significantly below the claimed 1-99 mol% 1-chloro-1,2-difluoroethylene range and above claimed 1-99 mol% 2,3,3,3-tetrafluoropropene range.
The rejection of claims 1 and 3-5 under 35 U.S.C. 103 as being unpatentable over Hashimoto et al. (JP 2015-145452 A) as previously set forth in the Office action mailed 07/08/2025 is maintained and has been revised below to reflect the changes in claim scope made by Applicant’s present claim amendments.
The rejection on the grounds of nonstatutory double patenting as being unpatentable over the claims of copending application 17/992,997 as previously set forth in the Office action mailed 07/08/2025 is maintained and has been revised below to reflect the changes in claim scope made by Applicant’s claim amendments in both the instant claims and the copending claims since the prior Office action.
Claim Interpretation
Applicant's definition of the term "azeotrope-like" on p.3 that "the term 'azeotrope-like' is intended in its broad sense to include both compositions that are strictly azeotropic and compositions that behave like azeotropic mixtures" is noted.
The transitional term "comprising" is inclusive or open-ended and does not exclude additional, unrecited components from the composition. The broadest reasonable interpretation of the claims reciting "comprising" language (e.g., claims 1 and 3-5) is an azeotrope/azeotrope-like composition comprising the recited amounts of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as well as any additional, unrecited components. See MPEP 2111.03, I.
It is noted newly added claim 6 recites further limits the azeotrope-like composition of claim 1 "consists essentially of" the 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene components. The transitional phrase "consisting essentially of" limits the scope of a claim to the specified materials or steps "and those that do not materially affect the basic and novel characteristic(s)" of the claimed invention. See MPEP 2111.03, III.
After careful review of the claimed invention's original disclosure, especially pages 3 and 4 of the original specification discussing the composition "may include additional components that do not form new azeotrope-like systems", the Office interprets claim 6 as being limited to compositions containing the recited amounts of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene and any additional component that does not form a new azeotrope-like system. In other words, the claim is limited to compositions where the 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene are the only azeotropic components present because additional azeotropic components fairly affect the basic and novel characteristics of the claimed invention.
Claim Objections
Claims 1 and 3-6 are objected to because of the following informalities: In all of the claims, Applicant is suggested to amend "1-chloro-1,2 difluoroethylene" to read as "1-chloro-1,2-difluoroethylene" (add a hyphen between "1,2" and "difluoroethylene") in order to improve clarity in the claims. The Examiner apologizes for not realizing this minor deficiency in the prior claim set.
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 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over Hashimoto et al. (JP 2015-145452 A). An English language machine translation of the reference is attached to the Office’s provided copy of the reference. Citations to the reference are with respect to the machine translation unless indicated otherwise.
Hashimoto et al. teach an azeotrope-like composition comprising trifluoroethylene and difluoromethane (abstract). The azeotrope-like composition comprises trifluoroethylene at a concentration of 1-99 wt.% and difluoromethane at a concentration of 1-99 wt.% (see near top of p.4 and claim 1). The azeotrope-like composition may further comprise optional components such as a hydrofluoroolefin (HFO) other than the trifluoroethylene and a hydrochlorofluoroolefin (HCFO) (bottom p.6). 2,3,3,3-tetrafluoropropene (HFO-1234yf) is an exemplary HFO other than the trifluoroethylene, and the content of the HFO other than the trifluoroethylene is preferably 1-20 wt.% of the composition (top p.7). 1-chloro-1,2-difluoroethylene (i.e., R-1122a) is an exemplary HCFO for the purpose of sufficiently suppressing flammability of the composition, and the content of the HCFO is preferably 1-20 wt.% of the composition (bottom p.7 to top p.8).
While Hashimoto et al. fail to meet the claimed composition under the meaning of anticipation, the claimed composition is nevertheless prima facie obvious over the cited teachings of the reference. At the time of the effective filing date it would have been obvious to provide/formulate an azeotrope-like composition comprising both 2,3,3,3-tetrafluoropropene and 1-chloro-1,2-difluoroethylene in effective amounts from the cited teachings of Hashimoto et al. in order to obtain an azeotrope-like working medium composition with a reasonable expectation of success.
The combination of the disclosed amounts of 1-20 wt.% 2,3,3,3-tetrafluoropropene as the additional HFO and 1-20 wt.% 1-chloro-1,2-difluoroethylene as the HCFO in the base/broad composition of 1-99 wt.% trifluoroethylene and 1-99 wt.% difluoromethane overlap the claimed, broad mol% concentrations of claim 1 as well as the molar ratio of 1-chloro-1,2-difluoroethylene to 2,3,3,3-tetrafluoropropene of about 10 to 90 (i.e., that there is approximately nine times more moles of 2,3,3,3-tetrafluoropropene than moles of 1-chloro-1,2-difluoroethylene). For example, a composition of 40 wt.% trifluoroethylene, 40 wt.% difluoromethane, 15 wt.% 2,3,3,3-tetrafluoropropene, and 10 wt.% 1-chloro-1,2-difluoroethylene is within the reference’s ranges and corresponds to a composition of about 32.7 mol% trifluoroethylene, about 51.6 mol.% difluoromethane, about 8.8 mol.% 2,3,3,3-tetrafluoropropene, and about 6.8 mol.% 1-chloro-1,2-difluoroethylene. Similarly, a composition of 63.2 wt.% trifluoroethylene, 20.4 wt.% difluoromethane, 14.9 wt.% 2,3,3,3-tetrafluoropropene, and 1.4 wt.% 1-chloro-1,2-difluoroethylene is within the reference’s ranges and corresponds to a composition of about 58.9 mol% trifluoroethylene, about 30 mol.% difluoromethane, about 10 mol.% 2,3,3,3-tetrafluoropropene, and about 1.11 mol.% 1-chloro-1,2-difluoroethylene; 10 is approximately nine times larger than 1.11.
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).
Double Patenting
Claims 1 and 3-6 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 2, 4, 5, and 9-18 of copending Application No. 17/922,997 (reference application).
Although the claims at issue are not identical, they are not patentably distinct from each other because both sets of claims recite compositions and products thereof comprising 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene. Independent claim 1 of the reference application recites a composition comprising 1-98 wt.% 1-chloro-1,2-difluoroethylene, 1-98 wt.% 2,3,3,3-tetrafluoropropene, and one of many genera/species of additional compounds. Some recited species of the additional compound are, for example and among others, carbon dioxide, ammonia, 1,1,1,2-tetrafluoroethane, and 1,1,1,2,3,3,3-heptafluoropropane. Compositions comprising any of these additional components (and very like many others) read on/overlap/encompass the claimed azeotrope-like composition and recited molar ranges of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene of claims 1 and 3-6, including the “consisting essentially of” language of dependent claim 6 as there is no evidence some minor amount of the third component would create a new azeotrope or destroy the azeotrope of the 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene components.
For example, a composition comprising 1-98 wt.% 1-chloro-1,2-difluoroethylene, 1-98 wt.% 2,3,3,3-tetrafluoropropene, and 1 wt.% carbon dioxide as encompassed and permitted by the copending claims corresponds to a composition comprising 1.1-96.9 mol.% 1-chloro-1,2-difluoroethylene and 0.9-96.3 mol.% 2,3,3,3-tetrafluoropropene and meets/overlaps the scope of the instant claims. Similarly, a composition comprising 1-98 wt.% 1-chloro-1,2-difluoroethylene, 1-98 wt.% 2,3,3,3-tetrafluoropropene, and 1 wt.% ammonia as encompassed and permitted by the copending claims corresponds to a composition comprising 1.1-93.6 mol.% 1-chloro-1,2-difluoroethylene and 0.8-92.6 mol.% 2,3,3,3-tetrafluoropropene and meets/overlaps the scope of the instant claims. Similarly, a composition comprising 1-98 wt.% 1-chloro-1,2-difluoroethylene, 1-98 wt.% 2,3,3,3-tetrafluoropropene, and 1 wt.% 1,1,1,2-tetrafluorethane as encompassed and permitted by the copending claims corresponds to a composition comprising 1.2-98.2 mol.% 1-chloro-1,2-difluoroethylene and 0.9-97.7 mol.% 2,3,3,3-tetrafluoropropene and meets/overlaps the scope of the instant claims. Similarly, a composition comprising 1-98 wt.% 1-chloro-1,2-difluoroethylene, 1-98 wt.% 2,3,3,3-tetrafluoropropene, and 1 wt.% 1,1,1,2,3,3,3-heptafluoropropane as encompassed and permitted by the copending claims corresponds to a composition comprising 1.2-98.7 mol.% 1-chloro-1,2-difluoroethylene and 0.9-98.4 mol.% 2,3,3,3-tetrafluoropropene and meets/overlaps the scope of the instant claims.
This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Response to Arguments
Applicant's arguments filed 01/08/2026 have been fully considered but they are not persuasive.
Applicant argues Hashimoto et al. (JP 2015-145452 A) discloses an azeotrope-like composition comprising two components not specified in independent claim 1, e.g., trifluoroethylene and difluoromethane, and that Hashimoto et al.’s focus is on azeotropic and azeotrope-like compositions comprising trifluoroethylene and difluoromethane rather than azeotropic and azeotrope-like compositions comprising 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as claimed.
In response, these arguments are not persuasive in view of the open-ended "comprising" language of the rejected claims that does not exclude additional, unrecited components from the composition. The broadest reasonable interpretation of the claims reciting "comprising" language (e.g., claims 1 and 3-5) is an azeotrope/azeotrope-like composition comprising the recited amounts of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as well as any additional, unrecited components. See MPEP 2111.03, I. While Hashimoto et al. indeed requires trifluoroethylene and difluoromethane, Hashimoto et al. further teaches/motivates the provision of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as additional components in the azeotrope-like composition which renders obvious the broad claims under a prima facie case of obviousness (Id.).
Applicant further argues Hashimoto et al. (allegedly per p.8 of the English transition) requires 1122 as the optional HCFO that is not the 1122a isomer as claimed. While Applicant’s argument is somewhat unclear as it does not specify the chemical names of the compounds (persons reading the record might not readily understand halocarbon abbreviation nomenclature), Applicant’s argument is interpreted as being Hashimoto et al. allegedly teach provision of 2-chloro-1,1-difluoroethylene (R-1122) rather than 1-chloro-1,2-difluoroethylene (R-1122a) as claimed.
In response, this argument is not persuasive because Hashimoto et al. very clearly teach provision of “1-chloro-1,2-difluoroethylene” which is the claimed R-1122a compound. Below is a copy of the compound disclosed by the reference at the end of the HCFO paragraph:
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Out of an abundance of caution to be sure the correct configuration was present/translated, the Office checked the original document and confirms that the reference also discloses the same “1” “1,2” substitutions in [0049]:
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1-chloro-1,2-difluoroethylene is the claimed compound. HCFO-1122 is merely Hashimoto et al.’s abbreviation/terminology for the 1-chloro-1,2-difluoroethylene compound and in no way detracts from the reference clearly teaching the claimed 1-chloro-1,2-difluoroethylene compound. While, in the art, the term "HCFO-1122" (rather than "HCFO-1122a") can refer to an abbreviation for 2-chloro-1,1-difluoroethylene (rather than 1-chloro-1,2-difluoroethylene, as claimed), the reference clearly states the compound is indeed “1-chloro-1,2-difluoroethylene” as claimed. Hashimoto et al. is very clear as to which constitutional isomer of chlorodifluoroethylene they intend/mean, and the stated constitutional isomer of chlorodifluoroethylene, “1-chloro-1,2-difluoroethylene” is the same precise constitutional isomer and compound as instantly claimed. The reference clearly teaches “1-chloro-1,2-difluoroethylene” as their only HCFO-1122 compound and no selection/step of choosing 1-chloro-1,2-difluoroethylene from 1-chloro-1,2-difluoroethylene and 2-chloro-1,1-difluoroethylene is required as alleged.
Applicant further argues Hashimoto et al.’s optional additional components are separate from the existing azeotrope-like composition comprising trifluoroethylene and difluoromethane, are not included in the azeotrope, and there is no presumption a composition comprising the optional 1-chloro-1,2-difluoroethylene (HCFO) and optional 2,3,3,3-tetrafluoropropene (HFO) components with azeotrope-like trifluoroethylene and difluoromethane blend is azeotropic or azeotrope-like.
In response, this argument is not persuasive because Hashimoto et al. clearly designates their compositions as azeotrope-like (abstract, etc., Id.). Provision of any and all additives in Hashimoto et al.’s prescribed/expressly disclosed amounts (e.g., the additional 1-chloro-1,2-difluoroethylene HCFO and 2,3,3,3-tetrafluoropropene HFO components) in the, overall azeotrope-like, open-ended composition comprising trifluoroethylene and difluoromethane would be very fairly expected by a person of ordinary skill in the art to maintain/present azeotrope-like properties. Following express teachings of a reference has a very reasonable presumption of satisfactorily modifying the reference (without rendering it unsatisfactory for its intended purpose) absent evidence to the contrary. Please note the open-ended "comprising" language of the rejected claims that does not exclude additional, unrecited components from the composition. The broadest reasonable interpretation of the claims reciting "comprising" language (e.g., claims 1 and 3-5) is an azeotrope/azeotrope-like composition comprising the recited amounts of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as well as any additional, unrecited components. See MPEP 2111.03, I.
These arguments are also attorney arguments that cannot take the place of evidence in the record. Applicant would need to submit a 132 declaration showing evidence a composition comprising 1-99 wt.% trifluoroethylene, 1-99 wt.% difluoromethane, 1-20 wt.% 2,3,3,3-tetrafluoropropene, and 1-20 wt.% 1-chloro-1,2-difluoroethylene is not azeotrope-like in any aspect. See In re De Blauwe, 736 F.2d 699, 705, 222 USPQ 191, 196 (Fed. Cir. 1984), In re Schulze, 346 F.2d 600, 602, 145 USPQ 716, 718 (CCPA 1965), In re Geisler, 116 F.3d 1465, 43 USPQ2d 1362 (Fed. Cir. 1997)
Applicant’s argument that Hashimoto et al.’s optional additional components are alleged as described as being in a separate composition from the azeotrope-like composition is noted but the Office cannot locate any such teachings in the reference. Nevertheless, this argument is moot because the components (required and optional) are all part of the same composition.
Applicant further argues while Hashimoto et al. teaches the possibility of optional components Hashimoto et al. teaches compositions where the sum of trifluoroethylene and difluoromethane are 100 mass% (i.e., consisting of the two components) are most preferable which clearly teaches the ordinary skilled artisan away from provision of additional HFOs and/or HCFOs as in the rejection of record.
This argument is not persuasive because preferred embodiments (such as Hashimoto et al.’s alleged preference for a composition consisting of trifluoroethylene and difluoromethane) do not constitute a teaching away from a broader disclosure, including less preferred or nonpreferred embodiments, (such as Hashimoto et al.’s disclosed express teachings to further provide 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as additional components in the trifluoroethane and difluoromethane-based azeotrope-like composition, Id.). See In re Susi, 440 F.2d 442, 169 USPQ 423 (CCPA 1971). "The use of patents as references is not limited to what the patentees describe as their own inventions or to the problems with which they are concerned. They are part of the literature of the art, relevant for all they contain." In re Heck, 699 F.2d 1331, 1332-33, 216 USPQ 1038, 1039 (Fed. Cir. 1983) (quoting In re Lemelson, 397 F.2d 1006, 1009, 158 USPQ 275, 277 (CCPA 1968)). A reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments. Merck & Co. v. Biocraft Labs., Inc. 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir. 1989), cert. denied, 493 U.S. 975 (1989).
Regarding the nonstatutory double patenting over the claims of copending Application No. 17/922,997 (reference application) Applicant requests the rejection be held in abeyance.
In response to Applicant’s request to hold in abeyance a response, such as, a terminal disclaimer to the provisional non-statutory double patenting rejection, it is noted that the filing of a terminal disclaimer cannot be held in abeyance since that filing “is necessary for further consideration of the rejection of the claims” as set forth in MPEP § 804 (I)(B)(1): “As filing a terminal disclaimer, or filing a showing that the claims subject to the rejection are patentably distinct from the reference application’s claims, is necessary for further consideration of the rejection of the claims, such a filing should not be held in abeyance. Only objections or requirements as to form not necessary for further consideration of the claims may be held in abeyance until allowable subject matter is indicated.”
Applicant also argues the reference application claims have been amended to require the presence of at least three components, 1-chloro-1,2-difluoroethylene, 2,3,3,3-tetrafluoropropene, and an additional component.
In response, this argument is not persuasive in view of the open-ended “comprising” language of the instant claims. The broadest reasonable interpretation of the claims reciting "comprising" language (e.g., claims 1 and 3-5) is an azeotrope/azeotrope-like composition comprising the recited amounts of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as well as any additional, unrecited components. See MPEP 2111.03, I. See also the revised nonstatutory double patenting showing compositions encompassed by the reference application claims indeed overlap the concentration ranges of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as instantly claimed. Furthermore, the reference application claims meet the “consisting essentially of” language of dependent claim 6 (limited to compositions where the 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene are the only azeotropic components present because additional azeotropic components fairly affect the basic and novel characteristics of the claimed invention) as there is no evidence some minor amount of the third component would create a new azeotrope or destroy the azeotrope of the 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene components. It is noted the two applications appear to have the same effective filing date. Timely filing of a Terminal Disclaimer or amending the instant claims to “consisting of” would overcome this rejection.
Accordingly, the rejections are maintained for the reasons of record.
Allowable Subject Matter
Claims 3, 4, and 6 are allowable over the prior art of record. However, note that all the claims are rejected under a nonstatutory double patenting rejection (Id.).
Claims 3, 4, and/or 6 would be would be allowable if: 1) they were rewritten in independent form including all of the limitations of the base claim and any intervening claims, and 2) Applicant addressed the double patenting rejection of record over copending Application No. 17/922,997.
The following is a statement of reasons for the indication of allowable subject matter: The closest prior art of record fail to teach or suggest an azeotrope-like composition comprising about 10-70 mol% of 1-chloro-1,2-difluoroethylene and about 30-90 mol% of 2,3,3,3-tetrafluoropropene (and subsets thereof) of claims 3 and 4. The closest prior art of record fail to teach or suggest an azeotrope-like composition consisting essentially of about 1-99 mol% of 1-chloro-1,2-difluoroethylene and about 1-99 mol% of 2,3,3,3-tetrafluoropropene (excluding any additional component that forms a new azeotrope-like system with or beyond the 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene components) of claim 6. Note the interpretation of claim 6’s “consists essentially of” language (Id.).
Hashimoto et al. (JP 2015-145452 A) teach an azeotrope-like composition comprising 1-99 wt.% trifluoroethylene and 1-99 wt.% difluoromethane (abstract, p.4, & claim 1). The azeotrope-like composition may further comprise optional components such as a hydrofluoroolefin (HFO) other than the trifluoroethylene and a hydrochlorofluoroolefin (HCFO) (bottom p.6). 2,3,3,3-tetrafluoropropene (HFO-1234yf) is an exemplary HFO other than the trifluoroethylene, and the content of the HFO other than the trifluoroethylene is preferably 1-20 wt.% of the composition (top p.7). 1-chloro-1,2-difluoroethylene (i.e., R-1122a) is an exemplary HCFO for the purpose of sufficiently suppressing flammability of the composition, and the content of the HCFO is preferably 1-20 wt.% of the composition (bottom p.7 to top p.8). This motivates/amounts to an azeotrope-like composition comprising 1-99 wt.% trifluoroethylene, 1-99 wt.% difluoromethane, 1-20 wt.% 2,3,3,3-tetrafluoropropene, and 1-20 wt.% 1-chloro-1,2-difluoroethylene.
However, the Hashimoto et al. fail to teach or suggest the claimed narrower concentrations of about 30-90 mol% and 60-90 mol% 2,3,3,3-tetrafluoropropene of instant claims 3 and 4 as the above wt.% concentrations, while permitting a maximum 1-chloro-1,2-difluoroethylene concentration of about 18.3 mol%, permit a maximum 2,3,3,3-tetrafluoropropene concentration of only about 15 mol% significantly below that claimed. The reference fails to further teach or suggest any guidance or reason to increase the 2,3,3,3-tetrafluoropropene/additional HFO component beyond 20 wt.% that would be necessary to even begin to approach the claimed about 30 mol% minimum concentration.
Hashimoto et al. also fail to teach, suggest, or meet the claimed “consisting essentially of” language of claim 6 as the transitional phrase fairly excludes any additional azeotropic component other than the 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene components. The reference’s azeotrope-like composition is based on and formed from the trifluoroethylene and difluoromethane components (e.g., abstract, p.4, etc.), meaning these components fairly and materially affect the basic and novel characteristic(s) of the claimed invention. There is no reason to exclude the azeotropic trifluoroethylene and difluoromethane components to arrive at a composition consisting essentially of 1-chloro-1,2-difluoroethylene and 2,3,3,3-tetrafluoropropene as they are required, base components in the reference’s composition.
Flaherty et al. (US 7,186,869 B2) teach a doped R-134a mixture comprising mostly R-134a (1,1,1,2-tetrafluoroethane) and several halocarbon impurity compounds, including 6 ppm c-A1122a (cis-1-chloro-1,2-difluoroethylene), 1 ppm t-A1122a (trans-1-chloro-1,2-difluoroethylene), and 14 ppm A1234yf (1,1,1,2-tetrafluoroprop-2-ene which is structurally the same as the claimed 2,3,3,3-tetrafluoropropene i.e. 2,3,3,3-tetrafluoroprop-1-ene) (see Example 1 & Table 1 in col. 5; see also the key for the abbreviations of these compounds in col. 1 especially lines 23-24 & 53-55). The disclosed 1 ppm 1-chloro-1,2-difluoroethylene and 14 ppm 2,3,3,3-tetrafluoropropene in a composition with 27 ppm of other impurities and the remainder 1,1,1,2-tetrafluoroethane is significantly below and outside each of the claimed 10-70 mol% 1-chloro-1,2-difluoroethylene and 30-90 mol% 2,3,3,3-tetrafluoropropene ranges, let alone the claimed 1-99 mol% 1-chloro-1,2-difluoroethylene and 1-99 mol% 2,3,3,3-tetrafluoropropene broader ranges. Flaherty et al. fail to teach or suggest any reason, motivation, or means of increasing the amounts of 1-chloro-1,2-difluoroethylene(s) and 2,3,3,3-tetrafluoropropene to approach the claimed ranges.
Merkel et al. (US 8,975,454 B2) teach a purified HFO-1234yf (2,3,3,3-tetrafluoropropene) product comprising 99.9671 wt.% HFO-1234yf and 3 ppm R-1122a (i.e., 1-chloro-1,2-difluoroethylene) as an impurity among other impurities (see Table 2 in col. 15). The disclosed 99.9671 wt.% HFO-1234yf and 3 ppm R-1122a in a composition with about 324 ppm of other impurities is significantly below the claimed 10-70 mol% 1-chloro-1,2-difluoroethylene range, let alone the broader 1-99 mol% range, and above claimed 30-90 mol% 2,3,3,3-tetrafluoropropene range, let alone the broader 1-99 mol% range. Merkel et al. fail to teach or suggest any reason, motivation, or means of increasing the amount of 1-chloro-1,2-difluoroethylene(s) and/while lowering the amount of 2,3,3,3-tetrafluoropropene to approach the claimed ranges.
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.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Correspondence
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/MATTHEW R DIAZ/Primary Examiner, Art Unit 1761
/M.R.D./
January 27, 2026