DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 03/02/2026 has been entered.
Response to Amendment
In response to the amendment received on 11/11/2025:
claims 1-16 are currently pending
claims 8-16 are withdrawn from consideration
claims 1, 8 and 13 are amended
new prior art grounds of rejection applying Huynh, Reid and Kondratowicz are presented herein
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 1-7 are rejected under 35 U.S.C. 103 as being unpatentable over Huynh et al. (US 8444763 B2), hereinafter referred to as HUYNH, in view of Reid et al. (US 10288597 B2), hereinafter referred to as REID, and Kondratowicz et al. (US 20190241472 A1), hereinafter referred to as KONDRATOWICZ, with evidence from Weng et al. (Effect of metakaolin on strength and efflorescence quantity of cement-based composite. The Scientific World Journal. 2013, Article ID 606524), hereinafter referred to as WENG, as to the rejection of claim 1.
Regarding claim 1, HUYNH teaches a geopolymer grout (Col. 5, lines 54-56: the geopolymer cement according to the invention may also be used in the manufacture of cement pastes and grouts), the geopolymer grout composition comprising metakaolin, fly ash and an activator mixture (Col 2, lines 35-38: a geopolymer cement comprising a metakaolin or a mixture of metakaolin and non-thermally activated aluminosilicate, and an alkaline silicate solution; and Col. 2, lines 45-47: “non-thermally activated aluminosilicate” selected from the group consisting of …, fly ash),
wherein the activator mixture comprising sodium hydroxide and sodium silicate (Col. 2, lines 62-67: the alkaline silicate solution may alternatively be obtained from a precursor solution adjusting an initial molar ratio M2O:SiO2 with an appropriate amount of alkaline hydroxide MOH; and Col. 2, line 53: M=Na),
wherein the Na2O:SiO2 molar ratio of the sodium silicate is between 0.40 and 0.70 (Col. 2, lines 39-40: an alkaline silicate solution having a molar ratio M2O:SiO2 comprised between 0.51 and 0.60, M representing Na or K).
Please note, the phrase “for protecting prestressing reinforcements” is a statement of intended use and not a positive limitation. Thus, the examiner treats the phrase “for protecting prestressing reinforcements” as not structurally limiting the geopolymer grout as set forth.
While HUYNH teaches a geopolymer cement comprising metakaolin having BET specific surface of metakaolin of approximately 19 m2/g (see HUYNH at Col. 3, lines 36-37), HUYNH fails to explicitly teach wherein the BET specific surface area of the metakaolin alone or of a mixture comprising the metakaolin and the fly ash is greater than or equal to 25 m2/g.
However, KONDRATOWICZ discloses a process for the preparation of geopolymer and geopolymer composite which does not require energy-intensive curing, drying and milling of the geopolymer as initially formed (see KONDRATOWICZ at paragraph [0016]). KONDRATOWICZ teaches a process for the preparation of geopolymer comprising the step a): mixing of an aluminosilicate, a phosphoaluminate, an alkaline silicate and/or an alkaline aluminate (see KONDRATOWICZ at paragraph [0045]), the mixing in step a) involves one or more materials selected from the group consisting of metakaolin, furnace slag, fly ash, or a mixture thereof, where an aluminosilicate component is mixed with an alkaline silicate solution prepared form sodium water glass (see KONDRATOWICZ at paragraphs [0051-52]). KONDRATOWICZ also teaches that an alkaline solution is prepared from a water solution of sodium hydroxide and silicon dioxide (water glass) or a water solution of sodium disilicate (see KONDRATOWICZ at paragraph [0053]); and that a molar ratio of M2O:SiO2 is comprised between 0.2 and 0.8, and the alkali metal silicate solution contains 45 to 65 wt.% of water (see KONDRATOWICZ at paragraph [0196]). Thus, KONDRATOWICZ discloses the geopolymer composite similar to the one disclosed by HUYNH. Additionally, KONDRATOWICZ teaches a step of jet milling the geopolymer composite to decrease particle size (see KONDRATOWICZ at paragraph [0164]); and that the geopolymer composite powder has a BET surface area in the range from 0.01 to 10000 m2/g (see KONDRATOWICZ at paragraph [0170]).
Furthermore, REID discloses the method of assessing the reactivity of s polymerizable material in forming a geopolymer (see REID at Abstract). REID teaches that metakaolin, fly ash, fluidized bed combustion bottom ash, treated reservoir sludge, slag, coal combustion bottom ash waste and prepared aluminosilicate are all examples of polymerizable materials; and that the reactivity of the polymerizable material typically affects the properties of the geopolymer formed from the polymerizable material (see REID at Col. 4, lines 48-55). REID also teaches that the reactivity of the polymerizable material in forming a geopolymer increases as the surface area increases (see REID at Col. 8, lines 6-8).
MPEP states that "[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", and “the normal desire of scientists or artisans to improve upon what is already generally known” (see MPEP § 2144.05(II)(A)). Thus, one of ordinary skill in the art would have recognized the potential benefit of improving the composition of HUYNH by adjusting the surface area of a composition comprising metakaolin to up to 10000 m2/g as disclosed by KONDRATOWICZ based on teachings of REID describing that the reactivity of the polymerizable material in forming a geopolymer increases as the surface area increases (see REID at Col. 8, lines 6-8).
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 modified the composition of HUYNH by adjusting the surface area of a composition comprising metakaolin to up to 10000 m2/g as disclosed by KONDRATOWICZ to reap the benefits of the increase of the surface area disclosed by REID such as increasing the reactivity of the polymerizable material in forming a geopolymer.
While HUYNH as modified by REID and KONDRATOWICZ is silent with respect to the claimed BET surface area of a mixture comprising metakaolin and fly ash reducing a viscosity of the geopolymer grout and limiting the apparition of efflorescence, HUYNH as modified by REID and KONDRATOWICZ teaches all structural limitations of claim 1 as set forth, thus, the properties of the resulting geopolymer composition are expected to be inherently disclosed (see MPEP §2112.01(I)). Furthermore, the beneficial properties of metakaolin are known in the art, as evidenced from the disclosure of WENG describing that metakaolin is increasingly being used to produce materials with higher strength, denser microstructure, lower porosity, higher resistance to ions, and improved durability (see WENG at Introduction, paragraph 3), and that specimen comprising metakaolin present greater resistance to efflorescence (see WENG at Abstract).
Regarding claim 2, HUYNH as modified by REID and KONDRATOWICZ teaches the geopolymer grout as claimed in claim 1, wherein the solution silicate has a mass content of water of between 52.1% and 72.1% (Col. 3, lines 27-28: the alkaline silicate solution generally has a water content by weight comprised between 55 and 63%), and the activator mixture has a mass content of water of less than 65% (Col. 6, lines 51-56: aqueous sodium silicate solutions are prepared from sodium silicate solution and solid sodium hydroxide; solution 1: 62.4% by weight of water). HUYNH teaches values which are within the claimed ranges.
Regarding claim 3, HUYNH as modified by REID and KONDRATOWICZ teaches the geopolymer grout as claimed in claim 2, wherein the activator mixture has a mass content of water of from 40% to less than 65% (Col. 6, lines 51-56: aqueous sodium silicate solutions are prepared from sodium silicate solution and solid sodium hydroxide; solution 1: 62.4% by weight of water). HUYNH teaches water content which is within the claimed range.
Regarding claim 4, HUYNH as modified by REID and KONDRATOWICZ teaches the geopolymer grout as claimed in claim 1, wherein the metakaolin:fly ash:alkaline silicate solution:sodium hydroxide mass ratio 1:1:2-3:0.15-0.35 (Table 1, Ex. 3: metakaolin 225 g, fly ash 225 g, alkaline activator solution 560 g). HUYNH teaches metakaolin:fly ash:alkaline silicate solution mass ratio of 1:1:2.5. Additionally, HUYNH teaches sodium silicate precursor solution (SiO2:Na2O by weight 3.25) and sodium hydroxide used to make an aqueous sodium silicate activator solution (Col. 6, lines 49-52), and that an alkaline silicate activator solution has a molar ratio M2O:SiO2 comprised between 0.51 and 0.60 (Col. 2, lines 62-67). Thus, HUYNH discloses the alkaline silicate solution:sodium hydroxide mass ratio 2.5:0.1-0.15 when sodium silicate precursor solution is adjusted by adding NaOH to obtain final activator solution having a molar ratio M2O:SiO2 comprised between 0.51 and 0.60 (Col. 2, lines 62-67). HUYNH teaches metakaolin:fly ash:alkaline silicate solution:sodium hydroxide mass ratio 1:1:2.5:0.10-0.15, which overlaps with the claimed range. In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim. See MPEP §2144.05(I).
Regarding claims 5 and 6, HUYNH as modified by REID and KONDRATOWICZ teaches the geopolymer grout as claimed in claim 1. The claimed properties such as grout exhibiting aqueous-solution bleeding less than 0.5% of the total mass of the grout (claim 5) and the grout having pH of between 13 and 14 (claim 6) are inherently disclosed because HUYNH as modified by REID and KONDRATOWICZ teaches all limitations of claim 1 as set forth. See MPEP §2112.01(I): “where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best”.
Regarding claim 7, HUYNH as modified by REID and KONDRATOWICZ teaches the geopolymer grout as claimed in claim 1, wherein the BET specific surface area of the metakaolin alone or of a mixture comprising the metakaolin and the fly ash is greater than or equal to 30 m2/g (see KONDRATOWICZ at paragraph [0170]: the geopolymer composite powder has a BET surface area in the range from 0.01 to 10000 m2/g). KONDRATOWICZ teaches a range which overlaps and renders obvious the claimed range.
Response to Arguments
Applicant’s arguments, see Remarks filed on 03/02/2026, with respect to the rejection(s) of claim 1 under 35 U.S.C. §103, as being unpatentable over JUSTICE and POULESQUEN have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of KONDRATOWICZ.
Conclusion
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/A.A.K./Examiner, Art Unit 1731
/ANTHONY J GREEN/Primary Examiner, Art Unit 1731
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