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 .
Information Disclosure Statement
Receipt is acknowledged of the Information Disclosure Statement filed 01 April 2024. The Examiner has considered the reference cited therein to the extent that each is a proper citation. Please see the attached USPTO Form.
Election/Restrictions
Applicant’s election of Group I (claims 52-59) without traverse in the reply filed on 18 September 2026 is acknowledged.
Claim 60-65 are withdrawn from consideration from further consideration pursuant to 37 CFR 1.142(b), as being withdrawn to a non-elected invention, and non-elected species of the invention, there being no allowable generic or linking claims.
Claims 52-59 are under examination and the requirement for restriction is made final.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 52-59 are rejected under 35 U.S.C. 103 as being unpatentable over Minor (US-20180179428-A1).
With regard to claims 52-53, Minor teaches a composition comprising: 56 to 72 wt.% 2,3,3,3-tetrafluoropropene (HFO-1234yf hereinafter); 8 to 39 wt.% difluoromethane (HFC-32 hereinafter); 5 to 20 wt.% 1,1, difluoroethane (HFC-152a hereinafter) (para [0088]). This disclosure overlaps with the claimed concentration ranges for HFO-1234yf, HFC-32, and HFC-152a.
Furthermore, Minor teaches that the composition may optionally include a hydrocarbon compatibilizer—such as propane, n-butane, or isobutane—in an amount of approximately 0.01 to 30 wt.% (paras [0189] and [0191]). This range overlaps with the claimed concentration ranges for the hydrocarbon group. Minor notes that this compatibilizer reduces the surface energy of metallic copper, aluminum, steel, or other metals and alloys found in heat exchangers, thereby reducing lubricant adhesion to the metal surfaces.
Minor does not teach a single embodiment with all the claimed elements together.
With regard to the hydrocarbon, it would have been obvious to a person of ordinary skill in the art before the effective filling date of the claimed invention to modify the composition of Minor. Specifically, to formulate a composition comprising HFO-1234yf, HFC-32, HFO-152a, and further comprising an optional compatibilizer such as propane, wherein HFO-1234yf is in an amount of 56 to 72 wt.%, HFO-32 is in an amount of 8 to 39 wt.%, and HFC-152a is in an amount of 5 to 20 wt.%, and the compatibilizer is in an amount of 0.1 to 30 wt.% of the composition. For doing so, Minor would guide one having ordinary skill in the art to employ a compatibilizer to reduce surface energy and adhesion to metallic surfaces (para [0191]). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filling date of the invention to have selected the overlapping portion of the ranges disclosed by the reference because selection of overlapping portion of ranges has been held to be a prima facie case of obviousness. See MPEP §2144.05(I). Therefore, the invention as a whole would be obvious to a person of ordinary skill in the art.
With regard to claim 54, Minor teaches that the composition can further comprise other hydrofluorocarbon comprising a saturated hydrofluorocarbon such as 1,1,1,2,2-pentafluoropropane (HFC-245cb), 1,1,1,2,3-pentafluoropropane (HFC-254eb), 1,1,1,2-tetrafluoroethane (HFC-134a), trifluoromethane (HFC-23), fluoromethane (HFC-41), 1,1,1-trifluoroethane (HFC-143a) (paras [0068-0069]), which read on c) as a combination of compounds specified in a) and b). Minor further teaches that at least one saturated HFC may also be included in the compositions in the range of from about 0 to 10wt.% (para [0080]).
With regard to claim 55, Minor teaches that the burning velocity of the compositions was evaluated relative to R-32 by measuring the pressure rise, noting an ISO-817 burning velocity of 6.7 cm/s for HFC-32 (para [0266]). Furthermore, Minor demonstrates that adding up to approximately 15 wt.% HFC-152a to H-32/HFO-1234yf compositions maintains a burning velocity below approximately 10 cm/s which is considered 2L flammability under ASHRAE Standard 34 (para. [0267]). This disclosure reads on the claimed burning velocity for the composition.
With regard to claim 56, Minor teaches that HFO-1234yf, HFC-32, and HFC-152a exhibit low flammability, classified as Class 2L under ASHRAE Standard 34-2010 (paras. [0061]–[0065]). Minor teaches that the preferred embodiments of the present invention generally exhibit 2L flammability and do not exceed Class 2 limits. Furthermore, Minor demonstrates that adding up to approximately 15 wt.% HFC-152a to H-32/HFO-1234yf compositions maintains a burning velocity below approximately 10 cm/s which is considered 2L flammability under ASHRAE Standard 34 (para. [0267]). This disclosure reads on the claimed flammability characteristics for the composition.
With regard to claim 57, Minor teaches that the composition may further comprise synthetic lubricants, including polyalkene glycol, polyol ester, poly alpha olefin, and polyvinyl ether (paras. [0177]–[0178]). This disclosure reads on the claimed lubricants.
With regard to claim 58, Minor teaches that the composition may include a stabilizer selected from nitromethane, ascorbic acid, terephthalic acid, azoles, phenols, terpenes, phosphites, phosphates, phosphonates, thiols, and lactones (para. [0193]). This disclosure reads on the claimed stabilizer.
With regard to claim 59, Minor teaches that the composition may further include a tracer, such as hydrofluorocarbons and perfluorocarbons (para. [0198]). This disclosure reads on the claimed tracer.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Aja A Walker whose telephone number is (571)272-0037. The examiner can normally be reached Monday - Friday 7-5.
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/A.A.W./Examiner, Art Unit 1761
/TANISHA DIGGS/Primary Examiner, Art Unit 1761
September 29, 2026
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