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 § 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.
Claim(s) 1 is/are rejected under 35 U.S.C. 103 as being unpatentable over Tan (CN 107032372), EPO translation.
Tan describes a process of extracting lithium hydroxide (para. 16) from lepidolite (para. 16) by roasting the lithium-containing ore (para. 17) in the presence of sulfuric acid (para. 40). The produced compound can include lithium sulfate (para. 89), which is then reacted with Ba(OH)2 (para. 45, described as step 4) at elevated temperatures of 80-85 degrees C (para. 78), which can be considered roasting temperature. The product made includes barium sulfate (para. 93). To the barium sulfate, an additional saturated LiOH solution is added to the mixture in order to adjust the pH (para. 87, 93). This can be considered a “dissolving the second mixture” step of Claim 1.
The solution is filtered to produce a filtered residue containing barium sulfate precipitate (para. 93). Since the barium sulfate residue is a solid, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that this salt is a precipitate, which meets the feature “to precipitate the insoluble barium sulfate” of Claim 1. As to the “insoluble” feature, since the compound is the same, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the same product has the same properties. As to the solid-liquid separation step, the filtration step of Tan can be considered to meet this feature.
The filtrate after separation of barium sulfate is LiOH (paga. 93), which is processed (para. 95) and then heated in a tiple effect evaporator (para. 97).
Claim(s) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Tan as applied to claim 1 above, and further in view of Liu (CN 110759372).
Tan does not describe the ratio of lithium sulfate to barium hydroxide used to make the barium sulfate.
Liu describes a method of making barium sulfate by reacting barium hydroxide with lithium sulfate, which are added in a ratio of 1:1-1.2 (abstract).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ a ratio of 1:1-1.2, as taught by Liu for use with the process of Tan because this ratio is effective to making barium sulfate.
References Made of Record
The following additional references from the examiner’s search are made of record:
Kim (KR 2016/0002578), EPO translation. Kim describes a method of making a lithium hydroxide product (para. 2). The process combines a lithium sulfate and barium hydroxide and reacts the two (para. 7) at elevated temperatures of 40 degrees C or higher (para. 10). The reaction causes insoluble barium sulfate precipitate to form and lithium hydroxide (para. 16).
Allowable Subject Matter
Claim 3 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is an examiner’s statement of reasons for allowance: Tan teaches heating up to 90 degrees C (para. 97) or roasting at temperatures of 850-950 degrees C (para. 89), but not at temperatures of 200-280 degrees C for 2-4 hours.
Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.”
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SHENG HAN DAVIS whose telephone number is (571)270-5823. The examiner can normally be reached 9-5:30.
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, Fung Coris can be reached at 571-270-5713. 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.
/SHENG H DAVIS/Primary Examiner, Art Unit 1732 September 5, 2025