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 .
Election/Restrictions
Applicant's election with traverse of group I, claims 1-8, in the reply filed on 17 December 2025 is acknowledged. The traversal is on the ground(s) that both invention groups substantially overlap each other. This is not found persuasive because, while overlap may exist between the groups, examination of group II with group I would require additional searching not required by examination of group I alone and would amount to an undue burden on the examiner.
The requirement is still deemed proper and is therefore made FINAL.
Claim Objections
Claim 2 is objected to because of the following informalities: Claim 2 refers to “the interconnected porous structure”, where claim 1 introduces “an interconnected porous matrix” (emphasis added). While the office understands them to be the same, Applicant should amend to maintain consistent terminology throughout the claims. Appropriate correction is required.
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 1-8 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.
The term “high-efficiency” in claim 1 is a relative term which renders the claim indefinite. The term “high-efficiency” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. It is unclear from the context of the claim and corresponding specification what objective metrics are necessary to be within the scope of “high-efficiency”.
The term “stable” in claim 1 (“stable evaporation”) is a relative term which renders the claim indefinite. The term “stable” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. It is unclear from the context of the claim and corresponding specification what characteristics are required to be within the scope of “stable.”.
The term “high” in claims 1 and 5 (“high salinity”) is a relative term which renders the claims indefinite. The term “high” is not defined by the claims, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. It is unclear from the context of the claims and corresponding specification what concentration of salt is required to be within the scope of “high salinity water”.
Claim 4 recites the limitation "the light absorption" in line 2. There is insufficient antecedent basis for this limitation in the claim.
Claim 5 recites the limitation "the temperature difference" in line 2. There is insufficient antecedent basis for this limitation in the claim.
Claim 5 recites the limitation "the high salt zone" in line 2. There is insufficient antecedent basis for this limitation in the claim.
Claim 5 recites the limitation "the bulk water" in line 2. There is insufficient antecedent basis for this limitation in the claim.
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 Wu et al (US 2022/0390147) in view of Li et al (“Highly Salt-Resistant 3D Hydrogel Evaporator for Continuous Solar Desalination via Localized Crystallization”) and Kuang et al (“A High-Performance Self-Regenerating Solar Evaporator for Continuous Water Desalination”).
Regarding claims 1-3, 5, 7 and 8, Wu discloses a buoyancy-driven convection based 3D solar evaporator for simultaneous salt rejection and evaporation of saline water, comprising (see Abstract; Fig. 3):
an interconnected porous matrix (hydrophilic fibrous layer 13) comprising polyvinyl alcohol (PVA) (see [0028]); and
a photothermal (light absorbing) material (layer 11) comprising graphene (see [0023]; [0029]).
Wu does not disclose wherein the 3D solar evaporator comprises (1) a funnel-shaped structure and (2) macrochannels on the outer surface.
Regarding (1), Li discloses a solar evaporator comprising a bilayer structure including a light absorber and a brine transport substrate, i.e., a photothermal material and a porous matrix, respectively (see pp. 1-2). A PVA hydrogel-based 3D evaporator achieves a stable solar desalination performance even in high-salinity brine by enabling edge-preferential salt crystallization. This advantage is observed due to the shape of the hydrogel, which is a conical frustrum (i.e., funnel-shaped) structure. The conical frustrum structure allows for radial brine transport in the evaporator, leading to edge-preferential salt crystallization, where conventional cylindrical shaped evaporators accumulate salt crystals all over the top surface and compromise sunlight absorption (see pp. 1-2).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to modify the solar evaporator of Wu by implementing the conical shape of the evaporator, as suggested by Li, in order to allow for radial brine transport and thus edge-preferential salt crystallization, thereby improving the light absorption performance of the evaporator.
Regarding (2), Kuang discloses a solar evaporator comprising millimeter-sized drilled channels which function as salt rejection pathways, allowing for improved efficiency and long-term stability (see Abstract).
It would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention to modify the solar evaporator of Wu by implementing millimeter-sized channels in the outer surface of the evaporator (i.e., macrochannels), as suggested by Kuang, in order to provide salt rejection pathways which have the effect of improving efficiency and stability of the evaporator.
Wu in view of Li and Kuang is considered to fully teach the structural features of the claimed apparatus. The intended manner of operating the apparatus is not considered to structurally distinguish the instant claimed invention over the prior art. MPEP 2114. However, the office notes that the cited references disclose evaporation of salt solutions having a salt concentration of at least 8 wt.% (see Li: p. 1; Kuang: p. 1).
The office additionally notes that Li discloses that the conical shape causes salt crystallization to concentrate on the outer perimeter of the surface, as described above. In other words, evaporation rate is improved (see p. 1). Furthermore, given that the combination of references discloses construction materials in line with those claimed, the corresponding evaporation rate and water absorption capabilities are reasonably expected to be as claimed. In the alternative, the office is of the position that selecting materials and construction which maximize evaporation rate and water absorption would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention. Absent a showing of new or unexpected results, the claimed evaporation rate and water absorption are not considered to patentably distinguish the instant claims over the cited prior art.
Regarding claim 4, Wu in view of Li and Kuang is considered to fully teach the structural features of the claimed apparatus, in particular where Li discloses that the conical shape causes salt crystallization to concentrate on the outer perimeter of the surface, as described above. In other words, the remainder of the surface is available for light absorption. Furthermore, given that the combination of references discloses construction materials in line with those claimed, the corresponding light absorption is reasonably expected to be as claimed. In the alternative, the office is of the position that selecting materials which maximize light absorption would have been obvious to a person of ordinary skill in the art at the time of filing the instant claimed invention. Absent a showing of new or unexpected results, the claimed light absorption is not considered to patentably distinguish the instant claims over the cited prior art.
Regarding claim 6, Kuang discloses the macrochannels having a diameter of approximately 1 mm (see p. 4, second paragraph).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RENEE ROBINSON whose telephone number is (571)270-7371. The examiner can normally be reached Monday - Thursday 8:00a-5:00p and Friday 8:00a-2:00p.
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/Renee Robinson/Primary Examiner, Art Unit 1772