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 .
Response to Amendment
The amendment filed on 01/20/2026 has been entered. Claims 1-4 and 6-20 are pending in the application. Claims 15-20 are withdrawn.
Applicant’s amendments to the claims have not introduced new matter and are supported in at least the prior claim set filed 09/22/2022.
Applicant’s amendments to the claims have overcome each and every 112(b) rejection previously set forth in the office action mailed 01/20/2026.
Response to Arguments
Applicant’s arguments, see Pg. 6-7, filed 01/20/2026, with respect to the 35 U.S.C. 112(b) rejections have been fully considered and are persuasive. The phrase “at least two precursor sols” in claim 1 provides sufficient antecedent basis for the phrase “precursor sols” in the subsequent claims 2-4, 8-9, and 11-13. The 35 U.S.C. 112(b) rejection of 09/17/2025 has been withdrawn.
Applicant's remaining arguments regarding the 103 rejections, filed 01/20/2026, have been fully considered but they are not persuasive.
Applicant argues on Pg. 7-8 that the prior art Wang teaches away from the instant invention and would lead a skilled artisan away from combination with the prior art Schwertfeger. Applicant argues Wang is directed to preparing neutral colloidal silicas with the goal of obtaining neutral or near-neutral pH values and that Wang does not disclose the formation of lyogels or any sol-gel transition intended to obtain a gel network.
However, in response to applicant's argument that Wang is nonanalogous art, it has been held that a prior art reference must either be in the field of the inventor’s endeavor or, if not, then be reasonably pertinent to the particular problem with which the inventor was concerned, in order to be relied upon as a basis for rejection of the claimed invention. See In re Oetiker, 977 F.2d 1443, 24 USPQ2d 1443 (Fed. Cir. 1992). In this case, Wang is directed to obtaining neutral colloidal silicon dioxide mixtures by adjusting pH with a basic colloidal silicate (Abstract; Pg. 5, par. 1). The instant invention requires mixing two precursor sols, one with acidic and another with a basic pH value, to obtain a mixed sol with a pH ranging from 4.5 to 9.5. A skilled artisan would understand the mixed sol pH ranging from 4.5 to 9.5 to encompass a neutral pH (i.e. pH) of 7. In this regard, the prior art Wang is directly applicable and is motivating to a skilled artisan in the manner it was applied. As described in the 103 section, a skilled artisan would be motivated to have the basic precursor being a colloidal silicic acid sol in the method of Schwertfeger due to the advantageous effect taught by Wang that the method is simple to operate and provides a very stable colloidal silica (Pg. 2, Disclosure of Invention).
Examiner notes Schwertfeger teaches the lyosol can be prepared with an acidic sol and a basic colloidal silicic acid, meeting the claim limitation. It was further noted that Schwertfeger also teaches the bases can include NH4O8 , NaOH, KOH, and Al(OH)3 ([0042]). In this regard, explicit motivation for selecting a colloidal silica specifically as the basic sol was provided by Wang.
Further, in response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In this case, the prior art Wang motivates a skilled artisan to use a basic precursor sol of colloidal silicic acid for the benefits of providing a simple operation method that provides a very stable colloidal silica (Pg. 2, Disclosure of Invention).
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 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.
Claims 1-2 and 4, 6-9 and 12-14 are rejected under 35 U.S.C. 103 as being unpatentable over Schwertfeger et al. (US20030207950A1) in view of Wang et al. (CN105778775A English).
Regarding claim 1, Schwertfeger teaches a method of producing substantially spherical lyogels in which a) a lyosol is made available, b) the lyosol obtained in step a) is transferred to at least one silylating agent in which the lyosol is insoluble, and c) the spherical lyosol formed in step b) is gelatinized in at least one silylating agent in which the lyosol is likewise insoluble, to produce the lyogel (Claim 1; Abstract). Schwertfeger teaches a lyogel is formed from sol (lyosol) (Claim 3) and that the produced gel particle obtained in step C can be used to produce aerogels ([0073]-[0074]). Schwertfeger teaches the lyosol obtained in step a) is obtained by adjusting the pH of an aqueous water glass solution to a pH value of ≤ 3 to obtain an acidic sol, where the pH of the lyosol can be increased by addition of a base to adjust the pH value to between 2 and 8, where the base used includes colloidal silicic acid ([0039]-[0042]). Schwertfeger teaches the pH of the lyosol can be increased by addition of a base to adjust the pH value to between 2 and 8, where the base used includes colloidal silicic acid ([0039]-[0042]). For clarity of record, Schwertfeger teaching the pH of the acidic sol is adjusted to a pH of up to 8 requires the pH of the base to be at least 8, meeting the limitation “the basic pH is in a range of pH 7 to 13, in particular pH 8 to 12, preferentially pH 9 to 11.”
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the ranges taught by Schwertfeger (acidic sol pH of ≤ 3; pH of basic sol up to 8; mixed sols displaying a pH between 2 and 8) overlaps with the claimed ranges (acidic sol pH 0 to 6; basic sol pH of 7 to 13; mixed sol pH in a range from 4.5 to 9.5). Therefore, the range in Schwertfeger renders obvious the claimed range.
The claim further requires producing a lyogel from “at least two precursor sols.” Schwertfeger teaches a lyosol can be obtained that is prepared with an acidic sol and a basic colloidal silicic acid, meeting the claim limitation. It is noted Schwertfeger also teaches the bases can include NH4O8 , NaOH, KOH, and Al(OH)3 ([0042]).
However, a skilled artisan would be motivated to select colloidal silicic acid as the basic sol component by the prior art Wang. Wang teaches a preparation method of neutral colloidal silicon dioxide where the pH of an acidic colloidal silica is adjusted to a pH of between 4-7 with a silicate base (Abstract; Claim 1; Pg. 5, par. 1).
Advantageously, the method of Wang is simple to operate and provides a very stable colloidal silica (Pg. 2, Disclosure of Invention).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to provide a silicate base as the basic component in the method of Schwertfeger in order to provide a very stable colloidal silica in a manner that is simple to operate, as taught by Wang.
Regarding claim 2, Schwertfeger in view of Wang teaches the method of claim 1 and Schwertfeger further teaches the lyosol can be incorporated into droplets, where the droplets can be added dropwise prior to gelation ([0062]-[0064]; [0066]-[0070]). Schwertfeger teaches the droplet addition rate may be adjusted to control the gelling rate and that the sols are mixed ([0053]; [0066]-[0067]). Accordingly, a skilled artisan could readily supply the droplets taught by Schwertfeger at a rate sufficient to control gelling, including providing the droplets in an immediate fashion, as required by the claim. A skilled artisan would be motivated to provide droplets in order to control the gelling rate of the subsequent sol, as taught by Schwertfeger ([0066]-[0067]). See MPEP 2144.05.II.
Regarding claim 4, Schwertfeger in view of Wang teaches the method of claim 1 and Schwertfeger further teaches a first acidic sol is obtained and the pH can then be adjusted by addition of a base, ([0039]-[0044]) meeting the limitation of providing separate solutions.
Regarding claim 6, Schwertfeger in view of Wang teaches the method of claim 1 and Schwertfeger further teaches the lyosol obtained in step a) is obtained by adjusting the pH of an aqueous water glass solution to a pH value of ≤ 3 to obtain an acidic sol ([0039]-[0042]). In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the range taught by Schwertfeger (pH value of ≤ 3) overlaps with the claimed range (acidic pH is in a range of pH 1 to 4). Therefore, the range in Schwertfeger renders obvious the claimed range.
Regarding claim 7, Schwertfeger in view of Wang teaches the method of claim 1 and Schwertfeger further teaches the pH of the lyosol can be increased by addition of a base to adjust the pH value to between 2 and 8, where the base used includes colloidal silicic acid ([0039]-[0042]). For clarity of record, Schwertfeger teaching the pH of the acidic sol is adjusted to a pH of up to 8 requires the pH of the base to be at least 8, meeting the limitation “the basic pH is in a range of pH 7 to 13, in particular pH 8 to 12, preferentially pH 9 to 11.” In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the range taught by Schwertfeger (pH of up to 8) overlaps with the claimed range (basic pH of 8 to 12). Therefore, the range in Schwertfeger renders obvious the claimed range. The Office notes that overlapping endpoints of a range are sufficient to support an obviousness rejection. See MPEP 2144.05.I.
Regarding claims 8-9, Schwertfeger in view of Wang teaches the method of claim 1 and Schwertfeger further teaches the pH of the lyosol can be increased by addition of a base to adjust the pH value of the lyosol to between 2 and 8 ([0041]). In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the range taught by Schwertfeger (pH between 2 and 8) overlaps with the claimed ranges (precursor sols comprise a pH value in a range from pH 4.5 to 9.5 (Claim 8); precursor sols comprise a weakly acidic pH in a range from 4.5 to 6.8 (Claim 9)). Therefore, the range in Schwertfeger renders obvious the claimed ranges.
Regarding claim 12, Schwertfeger in view of Wang teaches the method of claim 1 and Schwertfeger further teaches the acidic sol is obtained from aqueous water glass, that contains silicon ([0046]-[0047]) while the base can be colloidal silicic acid ([0042]).
The claim further requires the precursor sols comprise silicon-based precursors, which requires the basic sol to comprise silicon-based precursors. Schwertfeger clearly teaches colloidal silicic acid can be used as the base, meeting the limitation required by the claim, however Schwertfeger teaches the bases can also include NH4O8 , NaOH, KOH, and Al(OH)3 ([0042]).
However, a skilled artisan would be motivated to select colloidal silicic acid as the basic sol component comprising silicon. Wang teaches a preparation method of neutral colloidal silicon dioxide where the pH of an acidic colloidal silica is adjusted to a pH of between 4-7 with a silicate base (Abstract; Claim 1; Pg. 5, par. 1). A silicate base comprises silicon.
Advantageously, the method of Wang is simple to operate and provides a very stable colloidal silica (Pg. 2, Disclosure of Invention).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to provide a silicate base, which comprises silicon, as the basic component in the method of Schwertfeger in order to provide a very stable colloidal silica in a manner that is simple to operate, as taught by Wang.
Regarding claim 13, Schwertfeger in view of Wang teaches the method of claim 1 and 12 and Schwertfeger further teaches SiO2 content in the mixed sol (i.e. the sol comprising the acidic and basic components) is 5 to 12% by weight SiO2 ([0051]). Converting the SiO2 content to Si provides a Si content taught by Schwertfeger of about 2.3 to 5.6% (see calculations below). In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the range taught by Schwertfeger (mixed sol silicon content from about 2.3 to 5.6%) overlaps with the claimed range (precursor sols contain silicon in amounts in a range from 3 to 20 wt%). Therefore, the range in Schwertfeger renders obvious the claimed ranges.
Calculations: SiO2 molar mass = 60.08 g/mol
Si molar mass = 28.0855 g/mol
SiO2 molar mass in Si content = 28.0855/60.08 = 0.47
5 to 12 wt.% by SiO2 = 5*(0.47) to 12*(0.47) = 2.3 to 5.6% by Si
Regarding claim 14, Schwertfeger in view of Wang teaches the method of claims 1 and 12 and Schwertfeger further teaches the precursor sols include an acidic silica sol and a colloidal silicic acid as a basic component ([0039]-[0042]).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Schwertfeger et al. (US20030207950A1) in view of Wang et al. (CN105778775A English) and further in view of Suzuki et al. (US20090244709A1).
Regarding claim 3, Schwertfeger in view of Wang teaches the method of claim 1 and the claim further requires “the precursor sols for producing the lyogel are continuously mixed with each other.” Schwertfeger teaches “rapid thorough mixing of the two solutions takes place in apparatus with which a man skilled in the art is familiar, such as for example mixing vats, mixing jets and static mixers. Semi-continuous or continuous methods such as for example mixing jets, are preferred.” ([0053]). However, Schwertfeger does not explicitly mention the mixing is of the two precursor sols.
Suzuki teaches a method of preparing an aerogel coating that comprises preparing a first acidic sol and a second acidic sol and mixing the sols (Abstract). Suzuki teaches the first acidic sol is prepared using tetraalkoxysilane or its oligomer as the alkoxysilane, ammonia is preferably used as the base catalyst, and methanol is preferably used as the solvent ([0011]). The second acidic sol is preferably prepared using at least one selected from the group consisting of methyltrialkoxysilane, tetraalkoxysilane and their oligomers as the alkoxysilane, hydrochloric acid is preferably used as the acid catalyst for preparing the second acidic sol, and methanol and/or ethanol are preferably used as the solvent ([0012]). Suzuki teaches the first and second sols are mixed ([0051]-[0054]).
Advantageously, the mixed sols provide an aerogel with excellent scratch resistance and a low refractive index in a relatively short polymerization time ([0053]-[0054]; [0056]; [0079]).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to mix the two sols in the method of Schwertfeger in order to provide an aerogel with excellent scratch resistance and a low refractive index in a relatively short polymerization time as taught by Suzuki.
Claims 10-11 are rejected under 35 U.S.C. 103 as being unpatentable over Schwertfeger et al. (US20030207950A1) in view of Wang et al. (CN105778775A English) and further in view of Merz et al. (US3872217).
Regarding claims 10-11, Schwertfeger in view of Wang teaches the method of claim 1 and the claims further requires “the production of the lyogel is carried out at a pressure of less than 40 bar, in particular less than 30 bar, preferably less than 20 bar, more preferably less than 10 bar, particularly preferred at atmospheric pressure” and “the production of the lyogel from the mixed precursor sols takes place within less than 60 seconds, in particular less than 30 seconds, preferably less than 20 seconds, more preferably less than 10 seconds, further preferably less than 5 seconds.” Schwertfeger and Wang do not explicitly discuss the pressure and time of the lyogel formation from the sol.
Merz teaches a process for the manufacture of substantially spherical silica-containing hydrogels by reacting alkaline silica-containing raw materials with an acidic solution by providing droplets in a continuous-flow mixing zone that has pressure and time controls (Abstract; col. 4, lines 33-41). Merz teaches the mixing device for generating the hydrosol is performed under about 2 atmospheres and that when sprayed, the hydrosol solidifies into a hydrogel within about 1 second (col. 5, Example 1). A pressure of about 2 atmospheres is equal to about 2.02 bar. Additionally, a hydrosol and hydrogel are types of sols and lyogels, as understood in the art and further confirmed in the instant specification in at least Pg. 11, lines 3-20.
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. MPEP 2144.05 (I). In the instant case, the ranges taught by Merz (2 atmospheres, hydrogel formation in about 1 second) overlaps with the claimed ranges (pressure less than 40 bar (Claim 10); production of lyogel takes place within less than 60 seconds (Claim 11)). Therefore, the range in Merz renders obvious the claimed ranges.
Advantageously, the method of Merz, which includes pressure and gel formation durations within the claimed ranges, provides a solidified hydrogel that avoids drawbacks associated with long duration of hydrogel gel formation and formation of lumps that need to be broken up, which is highly complicated and very expensive (col. 1, lines 52-68; col. 2, lines 1-13).
Thus, prior to the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to form a hydrosol under a pressure of about 2 atmospheres and prepare a hydrogel in about 1 second in the method of Schwertfeger in order to provide a hydrogel in a short duration while avoiding lumps that require highly complicated and very expensive procedures to revert, as taught by Merz.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Jordan Wayne Taylor whose telephone number is (571)272-9895. The examiner can normally be reached Monday - Friday, 7:30 AM - 5 PM EST; Second Fridays Off.
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/J.W.T./Examiner, Art Unit 1738
/DANIELLE M. CARDA/Primary Examiner, Art Unit 1738 4/2/2026
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