Prosecution Insights
Last updated: April 19, 2026
Application No. 17/598,502

REFRIGERANT BLENDS IN FLOODED SYSTEMS

Final Rejection §103
Filed
Sep 27, 2021
Examiner
ARANT, HARRY E
Art Unit
3763
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
The Chemours Company Fc LLC
OA Round
4 (Final)
48%
Grant Probability
Moderate
5-6
OA Rounds
3y 9m
To Grant
71%
With Interview

Examiner Intelligence

Grants 48% of resolved cases
48%
Career Allow Rate
274 granted / 569 resolved
-21.8% vs TC avg
Strong +22% interview lift
Without
With
+22.4%
Interview Lift
resolved cases with interview
Typical timeline
3y 9m
Avg Prosecution
49 currently pending
Career history
618
Total Applications
across all art units

Statute-Specific Performance

§101
0.1%
-39.9% vs TC avg
§103
55.0%
+15.0% vs TC avg
§102
26.2%
-13.8% vs TC avg
§112
17.3%
-22.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 569 resolved cases

Office Action

§103
DETAILED ACTION 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 . Status of the Claims 2. The status of the claims as filed in the reply dated 2/21/2024 are as follows: Claims 1-12, 14, and 16-31 are canceled, Claim 13 is amended, Claims 32-38 are new, Claims 13, 15, and 32-38 are currently pending. Claim Rejections - 35 USC § 103 3. 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. 4. Claim(s) 13, 15, and 34-38 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bivens et al. (Bivens et al, “Performance of R-32/R-125/R134a Mixtures in Systems With Accumulators or Flooded Evaporators”,1997,ASHRAE Transactions, Vol. 103, 777-780 (Year: 1997), previously cited) in view of Tsuchiya et al. (U.S. Patent Publication No. 2020/0017742, “Tsuchiya” , previously cited). Regarding claim 13, Bivens discloses a method for replacing R-22 refrigerant in flooded evaporator refrigeration systems comprising: Providing a flooded evaporator refrigeration system that uses a first lubricant (page 778, col 1, lines 30-32), wherein the refrigeration system comprising a flooded evaporator is a chiller (see page 779, col 1, lines 20-39), replacing a first lubricant with a second lubricant, wherein the first lubricant is a mineral oil and the second lubricant is a polyol ester (POE) (page 778, col 1, lines 30-32); recovering the R-22 refrigerant from the system and charging with a non- azeotropic refrigerant (page 778, col 1, lines 30-32). However, Bivens does not explicitly disclose wherein the composition is selected from the group consisting of R-448A, R-449A, R-452A, R-454B, and R-454A. Tsuchiya, however, discloses a refrigeration system (fig 1) which may be a chiller (¶0036) and wherein a composition in the evaporator is selected from the group consisting of R-448A, R-449A, R-452A, R-454B, and R-454A (¶0033). Tsuchiya teaches that these refrigerants offer lower global warming potential that traditional refrigerants (¶0002-0005). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Bivens to have the composition be selected from R-448A, R-449A, R-452A, R-454B, and R-454A in order to reduce the global warming impact of the system. Regarding claim 15, the combination of Bivens and Tsuchiya discloses all previous claim limitations. Bivens does not explicitly disclose wherein the chiller is used for providing industrial or commercial air conditioning, cooling of industrial manufacturing processes, cold storage, food or pharmaceutical preparation, processing or preservation by cooling or freezing, or freezing an ice rink floor. However, the Examiner takes Official Notice that these applications are old and well known in the art of refrigeration and it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Bivens, as modified, to provide the Chiller in one of these applications. Regarding claim 34, the combination of Bivens and Tsuchiya discloses all previous claim limitations. Bivens, as modified, further discloses wherein the non-azeotropic composition is R- 448A (¶0033, Tsuchiya). Regarding claim 35, the combination of Bivens and Tsuchiya discloses all previous claim limitations. Bivens, as modified, further discloses wherein the non-azeotropic composition is R-R- 449A (¶0033, Tsuchiya). Regarding claim 36, the combination of Bivens and Tsuchiya discloses all previous claim limitations. Bivens, as modified, further discloses wherein the non-azeotropic composition is R-R- 452A (¶0033, Tsuchiya). Regarding claim 37, the combination of Bivens and Tsuchiya discloses all previous claim limitations. Bivens, as modified, further discloses wherein the non-azeotropic composition is R-R- 454B (¶0033, Tsuchiya). Regarding claim 38, the combination of Bivens and Tsuchiya discloses all previous claim limitations. Bivens, as modified, further discloses wherein the non-azeotropic composition is R- R- 454A (¶0033, Tsuchiya). 5. Claim(s) 32 and 33 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bivens and Tsuchiya as applied to claim 15 above, and further in view of Lenko (U.S. Patent Publication 2007/0125108). Regarding claim 32, the combination of Bivens and Tsuchiya discloses all previous claim limitations. Bivens, as modified, further discloses wherein the chiller for cooling a heat transfer fluid that transports the cooling to a remote location for chilling (as this is an inherent function of a chiller). However, Bivens as modified, does not explicitly disclose wherein the heat transfer fluid being an aqueous brine solution or a glycol. Lenko, however, discloses a method of cooling (fig 1) wherein a chiller for cooling a heat transfer fluid transports the cooling to a remote location for chilling (¶0031), the heat transfer fluid being a glycol (¶0032). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Bivens, as modified, to provide glycol as the heat transfer fluid in order to efficiently transfer the heat. Regarding claim 33, the combination of Bivens, Tsuchiya, and Lenko discloses all previous claim limitations. Bivens, as modified, does not explicitly disclose wherein the cooled heat transfer fluid is used for freezing an ice rink floor. Lenko, however, discloses a method of cooling wherein the cooled heat transfer fluid is used for freezing an ice rink floor (¶0031). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Bivens, as modified, to have the chiller freeze an ice rink floor such as taught by Lenko in order to efficiently utilize the system. Response to Arguments Applicant's arguments filed 12/42025 have been fully considered but they are not persuasive. Applicant argues (pages 3-5) that Tsuchiya teaches a mixture of refrigerant and thus does not teach the replacement of a refrigerant with one of a R-448A, R-449A, R-452A, R-454B, and R-454A. The Examiner respectfully disagrees; even if the refrigerant is not entirely one of the above refrigerant Tsuchiya still teaches the use of these refrigerants and thus meets the limitation. 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. Any inquiry concerning this communication or earlier communications from the examiner should be directed to HARRY E ARANT whose telephone number is (571)272-1105. The examiner can normally be reached Monday-Friday 10-6 ET. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jianying Atkisson can be reached at (571)270-7740. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /HARRY E ARANT/Primary Examiner, Art Unit 3763
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Prosecution Timeline

Sep 27, 2021
Application Filed
Nov 29, 2023
Non-Final Rejection — §103
Feb 21, 2024
Response Filed
Jun 01, 2024
Final Rejection — §103
Aug 08, 2024
Response after Non-Final Action
Oct 02, 2024
Notice of Allowance
Mar 03, 2025
Response after Non-Final Action
Mar 06, 2025
Response after Non-Final Action
May 31, 2025
Non-Final Rejection — §103
Dec 04, 2025
Response Filed
Jan 10, 2026
Final Rejection — §103 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

5-6
Expected OA Rounds
48%
Grant Probability
71%
With Interview (+22.4%)
3y 9m
Median Time to Grant
High
PTA Risk
Based on 569 resolved cases by this examiner. Grant probability derived from career allow rate.

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