DETAILED ACTION
Claims 1-20 were subjected to restriction requirement mailed on 03/25/2026.
Applicants filed a response, and elected Group I, claims 1-15 and 18-19, and withdrew claims 16-17 and 20, with traverse on 05/22/2029.
Claims 1-20 are pending, and claims 16-17 and 20 are withdrawn after consideration.
Claims 1-9, 11, 13-15 and 18 are rejected.
Claims 10, 12 and 19 are objected to.
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 claims 1-15 and 18-19 in the reply filed on 05/22/2026 is acknowledged. This is not found persuasive because the reason set forth below.
Applicants primarily argue:
“Applicant traverses the election on the basis that groups II-IV are directly linked to the process of claim 1 (Group IV -claim 20) or indirectly linked to the process of claim 1 via dependent claims 14 and 15 (Groups II and II, respectively). Accordingly, Groups II-IV have overlapping scope, via dependency, with the claims of Group I and therefore, there would not be a serious search and/or burden if restriction were not required.”
Remarks, p. 2
The examiner respectively traverses as follows:
Group II to IV are drawn to product claims, while claim 1 is a method claims. Group II to IV do not require all the limitations of claim 1.
Given Applicants have not traversed why none of the reasons given above and on pages 3-6 of the restriction requirement mailed on 03/25/2026 would not be proper, and given that Applicants have not traversed the Examiner’s explanation of all the inventions I to IV being independent or distinct for the reasons set forth on pages 3-6 of the restriction requirement mailed on 03/25/2026, the restriction requirement is proper.
The requirement is still deemed proper and is therefore made FINAL.
Claims 16-17 and 20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected Group, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 05/22/2026.
Specification
The disclosure is objected to because of the following informalities:
It is noted that the abstract filed 10/27/2023, line 6, recites a phrase “concerns”.
Applicant is reminded of the proper language and format for an abstract of the disclosure.
The abstract should be in narrative form and generally limited to a single paragraph on a separate sheet within the range of 50 to 150 words in length. The abstract should describe the disclosure sufficiently to assist readers in deciding whether there is a need for consulting the full patent text for details.
The language should be clear and concise and should not repeat information given in the title. It should avoid using phrases which can be implied, such as, “The disclosure concerns,” “The disclosure defined by this invention,” “The disclosure describes,” etc. In addition, the form and legal phraseology often used in patent claims, such as “means” and “said,” should be avoided.
Appropriate correction is required.
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 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) 1-7, 9, 11, 13 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Li et al., EP 3770115A1 (Li) in view of Anand et al., IN 202021056035A (Anand) (both provided in IDS received on 06/17/2024).
Regarding claims 1-6, 9, 11, 13 and 18, Li teaches a method for preparing an aqueous solution containing a silicate, using a rice hull ash (reading upon a plant ash and an inorganic alkali (Li, [0005]; [0010]);
the rice hull ash is produced by rice hull upon entering a boiler combustion zone (Li, [0057]);
as an example, the inorganic alkali is sodium hydroxide (reading upon a base), the water-soluble silicate is sodium silicate (Li, [0012]);
the rice hull ash and an aqueous solution of the aqueous solution of the inorganic alkali can be mixed and reacted (Li, [0011]), wherein the aqueous solvent of the aqueous solution of the inorganic alkali reads upon a dispersing medium.
Li further teaches in Examples 1-9, in preparation of white carbon black (i.e., silica from the silicate), the water glass mother liquor (i.e., sodium silicate) and sodium sulfate solution and water were mixed before acidifying with sulfuric acid to produce silica (Li, [0114] and [0115]). It therefore would have been obvious to a person of ordinary skill in the art to varying the order of addition of sodium sulfate solution and add the sodium sulfate solution (reading upon an additive, wherein said additive is a salt comprising a sulfur oxyanion) along with rice hull ash and the inorganic alkali when producing the silicate prior acidifying to produce silica, and yield expected results.
Further, it has been held that selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results, see MPEP 2144.04, section C, and also In re Burhans, 154 F.2d 690, 69 USPQ 330 (CCPA 1946), and In re Gibson, 39 F.2d 975, 5USPQ 230 (CCPA 1930).
Further regarding claim 1, Li does not explicitly disclose wherein said plant ash comprises crystalline silica and wherein at least a portion of said crystalline silica is cristobalite).
With respect to the difference, Anand teaches synthesis of silica from rice husk ash (Anand, page 2, 1st paragraph). Anand specifically teaches the characteristics of the rice husk ash are dependent on composition of the rice husks, burning temperature, burning time and type of boiler (Anand, page 2, bottom paragraph); a rice husk ash has cristobalite in a range of 1 to 50 wt%, quartz in a range of 1 to 10 wt.% and amorphous silica in a range of 50 to 98 wt.% (Anana, page 3, 1st paragraph).
Anand is analogous art as Anand is drawn to synthesis of silica from rice husk ash.
In light of the disclosure of Anand, it therefore would have been obvious to a person of ordinary skill in the art to use rice husk ash of varying characteristics in the preparing of silicate and silica of Li, including a rice husk ash has cristobalite in a range of 1 to 50 wt%, quartz in a range of 1 to 10 wt.% and amorphous silica in a range of 50 to 98 wt.%, dependent on composition of the rice husks, burning temperature, burning time and type of boiler, and thereby arrive at the claimed invention.
Regarding claim 7, as applied to claim 1, Li in view of Anand teaches a rice husk ash has cristobalite in a range of 1 to 50 wt%, quartz in a range of 1 to 10 wt.% (wherein cristobalite and quartz read upon crystalline silica; and the crystalline silica ranges from 2 to 50 wt.% of the total SiO2 content (i.e., (1+1)/(1+1+98)=2%; 50/(50+50)=50%);) and amorphous silica in a range of 50 to 98 wt.%, which overlaps with the presently claimed range.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Li in view of Anand as applied to claim 1 above, and further in view of Theunissen et al., EP 0363197A2 (Theunissen) (provided in IDS received on 06/17/2024).
Regarding claim 8, Li in view of Anand does not explicitly disclose wherein step (a) is carried out at a reaction temperature from 120 to 250 °C.
With respect to the difference, Theunissen teaches hydrothermal method of preparing sodium silicate (Theunissen, Abstract). Theunissen specifically teaches a method of preparing sodium silicate, by heating SiO2, caustic soda solution and water at above 150˚C (Theunissen).
As Theunissen expressly teaches, the hydrothermal method is capable of producing high molar SiO2/Na2O ratio (Theunissen, Abstract).
Theunissen is analogous art as Theunissen is drawn to hydrothermal method of preparing sodium silicate.
In light of the motivation of hydrothermal method of preparing sodium silicate as taught by Theunissen, it therefore would have been obvious to a person of ordinary skill in the art to prepare the silicate solution of Li in view of Anand, using the hydrothermal method of Theunissen, including at above 150˚C, in order to producing high molar SiO2/Na2O ratio, thereby arrive at a range the encompasses the range of the presently claimed.
As set forth in MPEP 2144.05, in the case where the claimed range “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists, In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Li in view of Anand as applied to claim 1 above, and further in view of Bacher et al., US 2020/0399134 A1 (Bacher) (provided in IDS received on 06/17/2024).
Regarding claim 14, as applied to claim 1, Li in view of Anand does not explicitly disclose wherein the process further comprises a step (b) of separating the silicate solution from the impurities deriving from the ash, said impurities comprising carbon products and metals.
With respect to the difference, Bacher teaches liquid silicate derived from rice hull and for use in the product of silica (Bacher, Abstract). Bacher specifically teaches upon reaction of rice ash with sodium hydroxide, there is separation system to remove undissolved solids, and purification system in order to produce high purity sodium silicate solution (Bacher, Figures 1-2); the combustion of the rice hulls can result in rice hull ash that contains greater than 90% silica and about 6% carbon. The rice hull ash also contains metallic impurities, such as calcium (Ca), iron (Fe), manganese (Mn), magnesium (Mg), potassium (K) and sodium (Na) (Bacher, [0006]);
As Bacher expressly teaches, attempts to pretreat the rice hulls prior to combustion have been reported to reduce these metallic impurities; however, these rice hull pretreatments appear to be expensive, time-consuming, and requires the use of large amounts of acid solutions (Bacher, [0006]).
Bacher is analogous art as Bacher is drawn to liquid silicate derived from rice hull and for use in the product of silica.
In light of the motivation of purifying sodium silicate derived from rice hull, as taught by Bacher, it therefore would have been obvious to a person of ordinary skill in the art, to remove impurities including carbon and metallic impurities, after sodium silicate is produced from rice hull, in order to use a less expensive, time-consuming, and without requiring the use of large amounts of acid solutions, and produce high quality sodium silicate, and thereby arrive at the claimed invention.
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Li in view of Anand as applied to claim 14 above, and further in view of Roggendort et al., Structural evolution of sodium silicate solutions dried to amorphous solids, Journal of Non-crystalline solids, 2001 (Roggendort).
Regarding claim 15, as applied to claim 15, Li in view of Anand does not explicitly disclose further comprising a step (c) of drying the silicate solution obtained after step (b) so as to obtain a silicate in solid form.
With respect to the difference, Roggendort teaches sodium silicate solution (Roggendort, Abstract). Roggendort specifically teaches for some applications the materials have to be dried, e.g., for their use as fire protecting layers in glazings (Roggendort, page 752, right column, 2nd paragraph).
Roggendort is analogous art as Roggendort is drawn to sodium silicate solution.
In light of the disclosure of Roggendort, it therefore would have been obvious to a person of ordinary skill in the art to dry the sodium silicate solution of Li in view of Anand and Bacher, for some applications and thereby arrive at the claimed invention.
Allowable Subject Matter
Claims 10, 12 and 19 are 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.
Regarding claim 10, none of Li, Anand, Theunissen, Bacher or Roggerdort discloses or suggests wherein the multivalent anion is selected from a dicarboxylate, a tricarboxylate and a combination thereof.
Regarding claim 12, none of Li, Anand, Theunissen, Bacher or Roggerdort discloses or suggests wherein said salt is sodium citrate (Na3C6H5O7), potassium citrate (K3C6H5O7), or a combination thereof.
Regarding claim 19, none of Li, Anand, Theunissen, Bacher or Roggerdort discloses or suggests redispersing the silicate in solid form in a dispersing medium, and (II) reacting the so-produced silicate solution and, optionally in addition at least one of a silicate solution other than the so-produced silicate solution, NaOH and a secondary silica source, with an acidifying agent to achieve precipitation of silica.
Conclusion
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/KELING ZHANG/
Primary Examiner
Art Unit 1732
Prosecution Insights