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 .
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 1-10 and 13-14 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. In this case, claim 1 recites “wherein the hydrogen halide gas is selected from hydrogen chloride and hydrogen bromide”, wherein such limitation encompasses the hydrogen halide gas being a mixture of hydrogen chloride and hydrogen bromide, but such subject matter is not described in the original disclosure. Rather instant specification describes “the hydrogen halide gas generated in the subsequent reaction process is single hydrogen halide, i.e., hydrogen chloride or hydrogen bromide thereby avoiding the generation of a mixture of hydrogen chloride and hydrogen bromide” (see filed specification in the published application US2023/0278862 para. [0034], [0046]). All claim 1’s depending claims are rejected for similar reasons.
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.
Claim 1-10 and 13-14 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. In this case, claim 1 recites “wherein the hydrogen halide gas is selected from hydrogen chloride and hydrogen bromide and is different from hydrogen fluoride”, such limitation is confusing because hydrogen chloride and/or hydrogen bromide apparently is different from hydrogen fluoride. All claim 1’s depending claims are rejected for similar reasons.
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 10 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. In this case, claim 10 recites in step (3) the reactor is a microreactor, but such limitation has been recited in its parent claim 1 already. Therefore, claim 10 does not further limit its parent claim. 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 Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 1-10 and 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Liu et al. (CN106745096) (for applicant’s convenience, Machine translations has been used for citations) in view of Wang et al. (CN102910612) (for applicant’s convenience, Machine translation has been used for citations).
Liu et al. teaches a process of forming alkali metal hexafluorophosphate comprising dissolving an alkali metal halide salt (e.g. lithium fluoride) to anhydrous hydrogen fluoride (claim 1-3, para. [0010]- [0012]), introducing (metering) phosphorus pentafluoride gas and alkali metal fluoride (in hydrogen fluoride) solution into a microchannel reactor and reacting under temperature of -10 to 30°C, wherein molar ratio of phosphorus pentafluoride to alkali metal fluoride introduced into the microchannel reactor is 1 to 3:1 (claim 1, 4, para. [0010], [0014], example 1-6). Liu et al. also teaches the obtained reaction product (containing solution) was filtered and flowed out of the reactor, then the resulting reaction product solution was evaporated (i.e. heated), cooled for crystallization, filtered and dried at 50-150 °C under normal pressure or 20-100 °C under reduced pressure (example 1-6). Liu et al. further teaches phosphorus pentafluoride and hydrogen fluoride can be completely removed under heating (phosphorous pentafluoride has a boiling point of -84.9 °C, hydrogen fluoride has a boiling point of 19 °C) (para. [0016]).
Regarding claim 1, Liu et al. does not expressly teach dissolving phosphorus pentahalide into an inert solvent to obtain a phosphorus pentahalide inert solvent solution, or the obtained reaction product (claimed a first mixture) comprising hydrogen halide gas being selected from hydrogen chloride and hydrogen bromide.
Wang et al. teaches a process of forming alkali metal hexafluorophosphate comprising adding PCl5 (phosphorous pentachloride) and lithium fluoride (an alkali metal halide) into a reactor, then dissolving PCl5 into an anhydrous inert solvent, slowly introducing high-purity hydrogen fluoride (HF) liquid from the bottom of the reactor to obtain PF5 (phosphorus pentafluoride), such produced PF5 dissolved in the anhydrous inert solvent reacting with lithium fluoride (LiF) to under temperature between 10-50°C to obtain lithium hexafluorophosphate (claim 1, para. [0012]-[0015], [0026],[0027], example 1-5, table 1). Wang et al. also teaches water will lead to by-product production, and the raw materials, solvents and reaction devices are all treated to remove water (para [0041]). Therefore, Wang et al. teaches using an anhydrous HF liquid. Hence, Wang et al teaches PF5 (phosphorus pentafluoride) dissolved in the anhydrous inert solvent reacting with LiF in the presence of anhydrous HF liquid to produce lithium hexafluorophosphate.
It would have been obvious for one of ordinary skill in the art to dissolve PF5 in an inert solvent as shown by Wang et al. to modify the process of Liu et al. because
applying a known technique using an inert solvent dissolving PF5 (phosphorus pentafluoride) as reactant to modify a known method of reacting PF5 with lithium fluoride for improvement would yield predictable results (see MPEP §2143 KSR).
Wang et al. further teaches HCl (hydrogen chloride) and excess HF generated during the reaction were discharged as gas, after the addition of HF was completed, the reaction was continued with stirring for 6 hours, and the solvent was filtered to obtain a mixed solvent containing lithium hexafluorophosphate (para. [0048]-[0058]). In summary, Wang et al. teaches the reaction product only having (i.e. consisting of) lithium hexafluorophosphate, HCl (hydrogen chloride), hydrogen fluoride and the inert solvent.
Since Wang teaches HCl being discharged as gas from the reaction product mixture therefore, a gas-liquid separation to remove HCl and obtaining a reaction product mixture consisting of lithium hexafluorophosphate, hydrogen fluoride and the inert solvent as that of instantly claimed is expected because it is hard to completely remove all HF in the reaction product mixture using a gas discharging. Wang et al. also teaches a lithium hexafluorophosphate solution containing an anhydrous organic solvent is obtained by filtration, and a lithium hexafluorophosphate solid product is obtained by evaporation and crystallization. Since evaporating involves removing solvent (i.e. fluid)- i.e. drying and solid-liquid separation on the mixture of a lithium hexafluorophosphate and the anhydrous organic solvent is expected.
It would have been obvious for one of ordinary skill in the art to adopt such well-known gas-liquid separation to remove HCl gas, and well-known solid-liquid separation on the mixture of a lithium hexafluorophosphate and the anhydrous organic solvent to remove the anhydrous organic solvent as shown by Wang et al. to modify the process of Liu et al. because adopting such well-known gas-liquid separation and solid-liquid separation to modify a well-known process of reacting PF5 with lithium fluoride obtaining lithium hexafluorophosphate for improvement (i.e. remove undesired byproduct of HCl gas etc. ) would yield predictable results (see MPEP §2143 KSR).
Furthermore, Liu et al. in view of Wang et al. teaches a substantially the same process as that of instantly claimed, and Liu et al. already teaches completely removing hydrogen fluoride) (para. [0016]).
Regarding claim 2 and 6, 9-10, 14, such limitations are met as discussed above.
Regarding claim 3, Wang et al. already teaches using phosphorus pentachloride as precursor dissolved in the anhydrous organic solvent to obtain phosphorous pentafluoride, since no chemical reaction can be achieved with 100% conversion, therefore, there are remaining phosphorus pentachloride dissolved in the anhydrous organic solvent still presented thereof. It would have been obvious for one of ordinary skill in the art to dissolve phosphorus pentachloride in the anhydrous organic solvent as shown by Wang et al. to modify the phosphorous pentafluoride reactant of Liu et al. because by doing so can help provide desired phosphorous pentafluoride reactant dissolved in the anhydrous organic solvent in-situ as suggested by Wang. Furthermore, adopting such well-known dissolving phosphorus pentachloride in the anhydrous organic solvent to modify a well-known method of reacting pentafluoride with LiF in the presence of HF obtaining lithium hexafluorophosphate for improvement would have predictable results (see MPEP §2143 KSR).
Regarding claim 4, Wang et al. further teaches the inert solvent can be dichloromethane (CH2Cl2) (a halogenated alkane) (para. [0048], [0058]), dichlorobenzene (para. [0054], [0055]).
Regarding claim 5, Wang et al. expressly teaches using 5000g of a mixed solvent of ether and dichloromethane (i.e. inert solvent), and 1306g of PCl5 (para. [0048]), wherein the mass of inert solvent is about 3.8 times as the mass of PCl5.
Regarding claim 7, Liu et al. further teaches the mass ratio of the alkali metal fluoride to the anhydrous hydrogen fluoride is 1:4-10 (claim 3, para. [0012], example 1-6).
Regarding claim 8, Liu et al. discloses dissolving alkali metal fluoride in the anhydrous hydrogen fluoride in a storage tank before being metered into the microreactor which has a reaction temperature from -10 to 30 °C (claim 1, 5, example 1-6). It would have been obvious for one of ordinary skill in the art to adopt such reaction temperature to dissolving the alkali metal fluoride in the anhydrous hydrogen fluoride for providing a reactant in the desired reaction temperature range.
Regarding claim 13, Wang et al. further teaches gas-liquid separation wherein HCl, HF gas being discharged out of reactor which has a reaction 10-50 °C, therefore, such gas being discharged with a temperature range of 10-50 °C which is overlapping with that of instantly claimed temperature range thus renders a prima facie case of obviousness (see MPEP § 2144. 05 I).
Claims 1-2, 5-10 and 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Wang’530 (CN114044530) (for applicant’s convenience, Machine translations has been used for citations) in view of Wang et al. (CN102910612) (for applicant’s convenience, Machine translation has been used for citations) and Liu et al. (CN106745096) (for applicant’s convenience, Machine translations has been used for citations).
Wang’530 teaches a method of preparing lithium hexafluorophosphate comprising: dissolve lithium fluoride in anhydrous hydrogen fluoride to obtain a lithium fluoride solution, under room temperature introducing (metering) phosphorus pentafluoride diethyl ether solution and lithium fluoride solution into a microchannel reactor at a lithium fluoride to phosphorus pentafluoride molar ratio of 1:1 to react and obtain a lithium hexafluorophosphate hydrogen, removing the diethyl ether solvent, after filtering the lithium hexafluorophosphate solution, the solution is cooled and crystallized to obtain lithium hexafluorophosphate crystals, which are then separated and dried to obtain the finished product (claim 1, para. [n0027], example 1-4).
Since Wang’530 already teaches a phosphorus pentafluoride diethyl ether solution, therefore, dissolving phosphorus pentafluoride into an inert solvent is expected.
As for the claimed first mixture consisting of hexafluorophosphate, hydrogen fluoride, the inert solvent and hydrogen halide gas, Wang’530 already teaches a same method of preparing lithium hexafluorophosphate via reacting a lithium fluoride solution with a lithium pentafluoride solution under the same temperature as that of instantly claimed, therefore, the same reaction mixture consisting of hexafluorophosphate, hydrogen fluoride, the inert solvent and hydrogen halide gas (e.g. hydrogen chloride) as that of instantly claimed is expected.
Regarding claim 1, Wang’530 does not expressly teach the gas-liquid separation to remove hydrogen halide gas, or removing hydrogen fluoride from the second mixture.
Wang et al. further teaches HCl (hydrogen chloride) and excess HF generated during the reaction were discharged as gas (para. [0048]-[0058]) wherein a gas-liquid separation for removing HCl from the first mixture is expected.
It would have been obvious for one of ordinary skill in the art to adopt such well-known gas-liquid separation to remove HCl gas as shown by Wang et al. to modify the process of Wang’530 because adopting such well-known gas-liquid separation to modify a well-known process of reacting PF5 with lithium fluoride obtaining lithium hexafluorophosphate for improvement (i.e. remove undesired byproduct of HCl gas) would yield predictable results (see MPEP §2143 KSR).
Liu et al. already teaches removing HF from a reaction mixture as described above.
It would have been obvious for one of ordinary skill in the art to adopt such well-known removing HF from the reaction product mixture as shown by Liu et al. to modify the process of Wang because adopting such well-known HF removal in the reaction product mixture to modify a well-known process of reacting PF5 with lithium fluoride obtaining lithium hexafluorophosphate for improvement would yield predictable results (see MPEP §2143 KSR).
Regarding claim 2, 6, 9-10, Wang’530 already teaches such limitations.
Regarding claim 5, Wang’530 further teaches the concentration of the phosphorus pentafluoride diethyl ether solution is 40-50 wt.% (claim 4, para. [n0017]), wherein such teachings suggest the concentration of diethyl ether concentration in such solution being 50-60 wt.%, therefore, the amount of inert solvent to the mass of phosphorus pentahalide is within or overlaps with the claimed range.
Regarding claim 7, Wang’530 further teaches the concentration of lithium fluoride in the lithium fluoride solution is 20-35wt% (claim 3, para. [n0016]), wherein such teachings suggest the solvent of anhydrous hydrogen fluoride concentration in such solution being 65-80 wt.%, therefore, the amount of anhydrous hydrogen fluoride to the lithium fluoride is within or overlaps with that of instantly claimed range.
Regarding claim 8, Wang’530 also discloses dissolving lithium fluoride in the anhydrous hydrogen fluoride and adjusting the temperature of the solution to 5-10°C (para. [n0010]).
Regarding claim 13, Wang et al. already teaches such HCl removing temperature range as described above.
Regarding claim 14, Liu et al. already teaches such HF removing temperate range.
Response to Arguments
Applicant’s amendments filed on 12/09/2025 have been acknowledged and thus previous objections and 112 rejections have been withdrawn.
Applicant’s arguments filed on 12/09/2025 have been fully considered and previous 103 rejections based on Wang et al in view of Liu et al. has been withdrawn. It is noted that Liu et al disclosed method is substantially the same as that of instant application using a microreactor metering lithium fluoride solution dissolved in HF to react with PF5. In response to applicant’s arguments about Liu no suggestion in Liu to integrate the hazardous PF5 synthesis step into the microreactor itself, the test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). In this case, Liu does not limit the microreactor reacting an inert solvent carried PF5 reacting with a lithium fluoride solution. On the contrary, Wang et al teaches in-situ generated PF5 in the inert solvent can react with lithium fluoride in the presence of HF. Therefore, adopting an inert carried PF5 as reactant to modify a well-known process of reacting PF5 with lithium fluoride just results naturally flowing from the applied references’ teachings.
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.
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/JUN LI/ Primary Examiner, Art Unit 1732