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 .
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.
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1-8, in the reply filed on 22 December 2025 is acknowledged.
It is noted that the restriction requirement set forth in the Office action mailed 26 November 2025 held that the inventions of Groups I and II lacked unity of invention in view of Duan et al. (CN 113603071). However, it is now recognized that this reference is not prior art, as it is the publication of the patent application to which the instant application claims foreign priority.
However, the finding that Groups I and II lack unity of invention is maintained: the shared technical feature recited in the last Office action--the method of claim 1--is not a special technical feature as it does not make a contribution over the prior art in view of either Zheng et al. (CN 112645299 A) and Wang et al. (CN 111704121 A), or in view of Gong et al. (CN 101708834 A), Wei et al. (CN 111908441 A) and Wang et al. (CN 111704121 A), as analyzed below.
Therefore, restriction between Groups I and II is still proper.
Claims 9-17 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 22 December 2025.
Information Disclosure Statement
The Information Disclosure Statement filed on 19 January 2024 has been received and considered by the Examiner.
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 3, 5, and 6 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.
Regarding claims 3 and 6, the phrase "preferably" renders the claims indefinite because it is unclear whether the limitations following the phrase are part of the claimed invention. See MPEP § 2173.05(d). For the purposes of further examination, limitation that are listed as preferable will be treated as optional.
Claim 5 recites the limitation "where in step (2), the acidic solution is…". There is insufficient antecedent basis for this limitation in the claim because step (2) or claim 1 does not recite any “acidic solution.” For the purposes of further examination, this limitations is interpreted as referring to the acidic solution in step (1) that is used to prepare the solution containing phosphorus and iron being used in step (2).
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 1-8 are rejected under 35 U.S.C. 103 as being unpatentable over Zheng et al. (CN 112645299 A) in view of Wang et al. (CN 111704121 A). The provided English machine translations of Zheng (CN 112645299 A) and Wang (CN 111704121 A) are relied upon in the analysis below.
The Zheng et al. reference applied in the following rejections shares a common applicant/assignee and certain inventors with the instant application. However, the additional authorship on the Zheng disclosure qualifies it as prior art under 35 USC 102(a)(1).
Additionally, Applicant cannot rely upon the certified copy of the foreign priority application to overcome this rejection because a translation of said application has not been made of record in accordance with 37 CFR 1.55. When an English language translation of a non-English language foreign application is required, the translation must be that of the certified copy (of the foreign application as filed) submitted together with a statement that the translation of the certified copy is accurate. See MPEP §§ 215 and 216.
Regarding claim 1, Zheng discloses a method for preparing a nano-sheet ferric phosphate, comprising the following steps:
(1) dissolving a phosphorus source and an iron source in an acidic solution to obtain a solution containing phosphorus and iron (dissolve the weighed ferric phosphorus in the hydrochloric acid solution at 20 °C, filter, and obtain an acidic ferric phosphorus solution; [0046]);
(2) heating part of the solution containing phosphorus and iron (Pour the diluted acidic iron-phosphorus solution into a precipitation reactor … heat the solution to 90 °C), adding a precipitation auxiliary agent (Preferably, in step (2), before heating, a precipitation aid is added to the acidic iron phosphorus solution; [0028]), and performing dilution (Add an appropriate amount of deionized water to the obtained acidic iron-phosphorus solution to control the iron and phosphorus concentration; [0047]) for a reaction to obtain a primary ferric phosphate slurry (to obtain a slurry containing iron phosphate precipitate; [0047]).
The nanosheet morphology of the ferric phosphate prepared by Zheng is evident in Figure 2 (copied below), and Zheng describes the particles as plate-like ([0050]).
While the embodiment of [0046] references above does not heat to boiling in step (2), Zheng further teaches that the temperature of step (2) can be 40°C-250 °C ([0019]), which includes temperatures at which the solution would boil, and also teaches that the heating function curve plays a role in regulating the nucleation process, thereby affecting the physical characteristics of the final precipitate, such as particle size and morphology ([0020]).
Therefore it would have been obvious to one of ordinary skill in the art to optimize the temperature in step (2) by routine experimentation to arrive at the method where the heating is performed to the boiling point of the solution.
Zheng does not teach after heating in step (2), adding a remaining portion of the acidic solution containing phosphorus and iron dropwise into the primary ferric phosphate slurry, and performing heating for a reaction to obtain ferric phosphate.
However, Wang also teaches a preparation method of iron phosphate nanosheets (small flaky primary particles; abstract). In particular, Wang teaches a feeding method where first a part of the phosphorus and iron source are used to synthesize iron phosphate and then the remaining iron-phosphorus mixture is added to the iron phosphate slurry at a rate of 0.4 mL/sec (1.5 L/h), which can be considered dropwise, and heated ([0024] and [0046]). Wang additionally teaches that such a feeding method improves the performance of lithium iron phosphate materials produced from it ([0072]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to heat only a portion of the acidic solution containing phosphorus and iron in step (2) of the method taught by Zheng, and to then add a remaining portion of the acidic solution containing phosphorus and iron dropwise into the primary ferric phosphate slurry, and perform heating for a reaction to obtain ferric phosphate, as taught by Wang. One of ordinary skill in the art would have been motivated to do so because Wang teaches that such a feeding method provides a ferric phosphate from which lithium iron phosphate with improved properties can be synthesized.
Regarding claim 2, modified Zheng teaches the method of claim 1, where Zheng also teaches filtering, washing, and drying the ferric phosphate ([0011]-[0012]).
Regarding claim 3, modified Zheng teaches the method of claim 1, where in step (1) the iron source is a ferric salt (ferric phosphate or ferric sulfate; [0013] and [0046]).
Regarding claim 4, modified Zheng teaches the method of claim 1, where in step (1) the phosphorus source can be phosphoric acid ([0013]).
Regarding claim 5, it is noted that the acidic solution in step (2) is being interpreted the acidic solution in step (1), which is used to prepare the solution recited in step (2) (see Claim Rejections – 35 USC § 112). Modified Zheng teaches the method of claim 1, where the acidic solution is hydrochloric acid ([0046]).
Regarding claim 6, modified Zheng teaches the method of claim 1, where in step (2) water is added for dilution during the dilution (add an appropriate amount of deionized water; [0047]). Zheng further teaches that the final concentration of iron and phosphorus is 1.0 mol/L, and that the initial concentration of iron and phosphorus in the acid solution 80 g FePO4 in 120 mL of solution ([0046]). This corresponds to an iron concentration of 0.53 mol per 0.12 L, or 4.4 mol/L. To achieve a concentration of 1.0 mol/L, the total volume of the added water to the volume of the part of the solution containing phosphorus and iron must be 3.4:1, which falls in the instantly claimed range of (2-20):1.
Regarding claim 7, modified Zheng teaches the method of claim 1, where in step (2) the precipitation auxiliary agent (precipitation agent) can be titanium dioxide ([0029]).
Regarding claim 8, modified Zheng teaches the method of claim 1, but neither Zheng nor Wang explicitly teach adding a precipitating agent during step (3). However, Zheng does teach that the precipitating agent serves to help overcome energy barriers associated with precipitation and to ensure uniformity of doping.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to add the precipitation auxiliary agent into the remaining solution containing phosphorus and iron before adding the remaining solution containing phosphorus and iron into the primary ferric phosphate slurry. One of ordinary skill in the art would have been motivated to do so because continued precipitation is occurring during step (3) and having the precipitating agent present would help to ensure uniform doping of the element in the precipitating agent.
Claims 1-5 and 7-8 are rejected under 35 U.S.C. 103 as being unpatentable over Gong et al. (CN 101708834 A) in view of Wei et al. (CN 11908441 A) and Wang et al. (CN 111704121 A). The provided English machine translations of Gong (CN 101708834 A), Wei (CN 11908441 A), and Wang (CN 111704121 A) are relied upon in the analysis below.
Regarding claim 1, Gong discloses a method for preparing a nano-sheet ferric phosphate (disc-shaped iron phosphate powder; [0002]), comprising the following steps:
(1) dissolving a phosphorus source and an iron source in an acidic solution to obtain a solution containing phosphorus and iron (Add 1 liter of deionized water pre-adjusted to pH=1 with nitric acid to a stirred reactor, then add 40.4 g (0.1 mol) Fe(NO3)3·9H2O with stirring. After Fe(NO3)3·9H2O has dissolved, add 14.2 g (0.1 mol) Na2HPO4; [0021]);
(2) heating part of the solution containing phosphorus and iron to obtain a primary ferric phosphate slurry (reactor solution was heated to 80°C and reacted at this temperature for 3 hours to obtain a white suspension; [0021]).
Regarding heating the solution to boiling, as required by the instant claim, Gong further discloses that the temperature in this step should be in the range of 80 °C-100°C ([0010]), and the boiling point of the aqueous solution is expected to be approximately 100 °C. Therefore this range overlaps, or very nearly overlaps, with the instantly claimed temperature.
Generally, differences temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating that such a temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." See MPEP 2144.05 and In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). Therefore, the claimed conditions of heating to boiling merely represent an obvious variant and/or routine optimization of the temperature values of the cited prior art.
Gong additionally teaches adjusting the pH of the solution to 1-1.5 with nitric acid ([0021]), which involves the addition of additional solvent and therefore meets the limitation of performing a dilution, as required by the instant claim.
Gong does not teach adding a precipitation auxiliary agent, or after heating in step (2), adding a remaining portion of the acidic solution containing phosphorus and iron dropwise into the primary ferric phosphate slurry, and performing heating for a reaction to obtain ferric phosphate.
However, Wei also teaches a preparation method of iron phosphate (titanium-doped iron phosphate; title) and further teaches that a precipitation auxiliary agent (titanium sulfate; [0041]) can be added to a phosphorus and iron containing solution ([0032]-[0033]) to create a uniform doping effect ([0025]). Wei additionally teaches that doping can improve the material’s performance in power and energy storage applications ([0004]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Gong to include adding the precipitation auxiliary agent of titanium sulfate, as taught by Wei. One of ordinary skill in the art would have been motivated to do so because the precipitation auxiliary agent would allow for the generation of uniformly titanium-doped iron phosphate and increased performance, as taught by Wei.
Furthermore, Wang also teaches a preparation method of iron phosphate nanosheets (small flaky primary particles; abstract). In particular, Wang teaches a feeding method where first a part of the phosphorus and iron source are used to synthesize iron phosphate and then the remaining iron-phosphorus mixture is added to the iron phosphate slurry at a rate of 0.4 mL/sec (1.5 L/h), which can be considered dropwise, and heated ([0024] and [0046]). Wang additionally teaches that such a feeding method improves the performance of lithium iron phosphate materials produced from it ([0072]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to heat only a portion of the acidic solution containing phosphorus and iron in step (2) of the method taught by Zheng, and to then add a remaining portion of the acidic solution containing phosphorus and iron dropwise into the primary ferric phosphate slurry, and perform heating for a reaction to obtain ferric phosphate, as taught by Wang. One of ordinary skill in the art would have been motivated to do so because Wang teaches that such a feeding method provides a ferric phosphate from which lithium iron phosphate with improved properties can be synthesized.
Regarding claim 2, modified Gong teaches the method of claim 1, where Gong also teaches filtering, washing, and drying the ferric phosphate (After cooling and filtration, the filter cake was washed three times with deionized water. The filter cake was then dried in an oven at 100-120°C for 6 hours to obtain iron phosphate powder; [0021]).
Regarding claims 3 and 4, modified Gong teaches the method of claim 1, where in step (1) the iron source is a ferric salt (Fe(NO3)3·9H2O) and
the phosphorus source is hydrogen phosphate (Na2HPO4; [0021]).
Regarding claim 5, it is noted that the acidic solution in step (2) is being interpreted the acidic solution in step (1), which is used to prepare the solution recited in step (2) (see Claim Rejections – 35 USC § 112). Modified Gong teaches the method of claim 1, where the acidic solution is nitric acid ([0021]).
Regarding claim 7, modified Gong teaches the method of claim 1, where Wei teaches in step (2) the precipitation auxiliary agent is titanium sulfate ([0041]).
Regarding claim 8, modified Gong teaches the method of claim 1, but neither Gong nor Wang explicitly teach adding a precipitating auxiliary agent during step (3).
However, Wei teaches that it is desirable to have uniform doping in the materials being produced and that the titanium source (precipitating auxiliary agent) can be uniformly dispersed using a method where it present in the iron and phosphorus containing solution ([0055] and [0061]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the titanium salt present in both solutions containing iron and phosphorus in the method of modified Gong, including the remaining solution being added in step (3). One of ordinary skill in the art would have been motivated to do so in order to achieve uniform doping of the product iron phosphate.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Gong et al. (CN 101708834 A) in view of Wei et al. (CN 11908441 A) and Wang et al. (CN 111704121 A), as applied to claim 1 above, and further in view of Chen et al. (CN 110294466 A). The provided English machine translations of Gong (CN 101708834 A), Wei (CN 11908441 A), Wang (CN 111704121 A), and Chen (CN 110294466 A) are relied upon in the analysis below.
Regarding claim 6, modified Gong teaches the method of claim 1, where in step (2) nitric acid or sodium hydroxide are added to adjust pH ([0010]), which will result in dilution; nitric acid is an aqueous solution which will contain water. Gong does not teach a volume ratio of the added water to the part of the solution containing phosphorus and iron being in the range of (2-20):1.
However, Chen also teaches the preparation of nanosheet ferric phosphate (title), and further teaches that the solution concentration has an effect on the morphology of the iron phosphate ([0020]).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to optimize by routine experimentation the amount of water being added during the dilution, including into the claimed range of (2-20):1 for a ratio of the added water to the part of the solution containing phosphorus and iron. One of ordinary skill in the art would have been motivated to do so because Chen teaches that the solution concentration has an effect on the morphology of the iron phosphate produced, which is something that Gong also wants to control (a method for preparing disc shaped iron phosphate powder; [0002]).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Nicholas A Piro whose telephone number is (571)272-6344. The examiner can normally be reached Mon-Fri, 8:00 am-5:00 pm.
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/NICHOLAS A. PIRO/Assistant Examiner, Art Unit 1738
/PAUL A WARTALOWICZ/Primary Examiner, Art Unit 1735