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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 12/29/2025 has been entered.
Election/Restrictions
Claims 1-4, 6-7 and 15-17 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 1/3/2025.
Response to Amendment
The amendment filed on 12/29/2025 has been entered. Claim(s) 8, 22 and 27 is/are currently amended. Claim(s) 5 and 13-14 has/have been cancelled. Claim(s) 1-4, 6-12, 15-31 is/are pending with claim(s) 1-4, 6-7 and 15-17 withdrawn from consideration. Claim(s) 8-12, and 18-31 is/are under examination in this office action.
Response to Arguments
Applicant's argument filed on 12/29/2025, with respect to 103 rejection has been fully considered but is not persuasive.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
Applicant argued that the claims are amended to incorporate details of the aerogels produced by the claimed processes that contribute to the results shown in Fig. 3, which the Examiner recognized in the Final Office Action appeared inventive. None of the cited prior art references, alone or in combination, discloses or suggests aerogels produced using the processes as recited in independent claims 8, 22, and 27 as amended.
In response, the Final Office Action did not indicate any inventive subject matter shown in Fig. 3. The cited prior art references teach or suggest the recited processes as stated in the 103 rejection of the present office action.
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 8-12, and 18-31 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 “substantially” in claim 8 is a relative term which renders the claim indefinite. The term “substantially” 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. For the purpose of further examination, based on the broadest reasonable interpretation, this term is considered not necessary.
Claim 8 recites “other elements of the emulsion” which renders the claim indefinite because it is not clear what elements are the “other elements” referring to. For the purpose of further examination, based on the broadest reasonable interpretation, any elements of the emulsion will be considered meeting this limitation.
Claims 9-12, and 18-31 are rejected likewise as depending on claim 8.
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 text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
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) 8-12 and 18-31 is/are rejected under 35 U.S.C. 103 as being unpatentable over Sachithanadam et al (WO 2019070193 A1) in view of Breitenbach et al (US 5945032 A), Xiang et al (CN 106839661 A, machine translation is referenced herein), and Xu et al (CN 108097180 A, machine translation is referenced herein).
Regarding claim 8, Sachithanadam teaches a method of manufacturing a silica aqueous aerogel composite [abstract], comprising the steps of
a) providing an aqueous solution comprising a water soluble polymeric binder and a surfactant;
b) adding a silyl-modified silica aerogel to the aqueous solution to form a first mixture; c) adding a water soluble crosslinking agent to the first mixture to form a second mixture;
d) freeze-drying the second mixture at a first pre-determined pressure and at a first pre-determined temperature suitable for sublimation of ice to form a composite;
e) curing the composite [claim 1].
The examiner submits that the step a) reads on the claimed “synthesizing an aqueous binder mixture” because the binder and a surfactant form a mixture.
According to the applicant, silyl modified precursors can be prepared from a commercially available silica aerogel, and the silica aerogel may undergo partial or full wetting by using surfactants to facilitate interactions between hydrophilic and hydrophobic groups during the emulsion stage [P12L34-P13L2 spec.]. Sachithanadam teaches using an as bought silica aerogel being modified by silyl groups and dispersing in the solution [P23L13-16]. Therefore, the step b) of adding a silyl-modified silica aerogel to the aqueous solution containing a surfactant is the same as the applicant’s step of “adding silyl modified precursors to form an emulsion”.
According to the applicant, chemical crosslinking may be used to promote the formation of a three-dimensional network of turning silyl- modified precursor emulsion into gelled composites [P13L13-14 spec.]. Therefore, the step c) of Sachithanadam reads on the claimed “forming a gelled composite”, as Sachithanadam teaches that the crosslinking agent promotes forming a three-dimensional network of the aerogel composite [P8L12-14, P24L9-10].
Sachithanadam teaches adding a crosslinking agent about 0.5 wt% to about 10 wt% of the final composite weight [P29L20-21], meeting the claimed “adding a water-soluble crosslinking agent in an amount ranging from 0.5% - 10% of a final composite weight of the gelled composite”.
Sachithanadam teaches that the rate of crosslinking is dependent on the reactivity of the groups and the temperature of the solution to promote the formation of a three-dimensional network [P24L11-13], meeting the claimed “at a rate dependent at least in part on reactivity of the crosslinking agent used and temperature of the emulsion to thereby promote formation of a three-dimensional network within the gelled composite”.
The step c) does not include a vacuum homogenizing. However, Breitenbach teaches a gel complex [col.8, line 25-26] prepared in a vacuum homogenizer to give a gel free of air bubbles [col.11, line 26-29].
It would have been obvious to one of ordinary skill in the art at the time of filing to use vacuum homogenizing process in Sachithanadam’s method for the benefit of obtaining a gel free of air bubbles.
Sachithanadam teaches that the method further including the steps of coating the cured composite with a hydrophobic material (e.g., a silane coupling agent) which will react with the hydrophilic functional groups and render then hydrophobic, and thus turn the aerogel hydrophobic and thus giving the aerogel composite a better shelf-life [P16L21-P17L6]. This reads on the claimed “treating the gelled composite hydrophobically… by infusing the gelled composite with a water-based coupling agent to react with any hydrophilic functional groups within the gelled composite and render them hydrophobic, thereby giving the water-based hydrophobic aerogels or aerogel composites a longer shelf-life”. Since vacuum homogenizing can be applied during gel making as stated above, it would have been obvious to one of ordinary skill in the art at the time of filing to coat the gel in situ under vacuum homogenizing, because selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results. In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930). MPEP 2144.04.IV(C).
Sachithanadam teaches freeze-drying at the first predetermined pressure of 100-400 Pa [P12L31-32], which is a vacuum pressure. Therefore, the step d) reads on the claimed “freezing the gelled composite” and “vacuum freeze-drying the gelled composite to form an aerogel composite”.
Sachithanadam does not teach that the freeze-drying is “microwave assisted”. However, in the same field of endeavor, Xiang teaches microwave vacuum freeze drying of hydrogel [P10L24-25]. Microwave vacuum freeze drying has various advantages of avoiding long drying cycle, large energy consumption, uneven heating [P2L11-28]. It would have been obvious to one of ordinary skill in the art at the time of filing to apply microwave vacuum freeze-drying in Sachithanadam’s method for the aforementioned advantages.
Xiang teaches that the emission power of the microwave is controllable to ensure the drying effect of material [P5L35-36]. One of ordinary skill in the art would understand that the drying effect of material depends at least in part on weight of the material and on an amount of aqueous content in the material. Therefore, the recited “the first input energy being based at least in part on weight of the frozen gelled composite … and on an amount of aqueous content in the frozen gelled composite” is obvious.
Xiang is silent about the claimed range of 0.5-2.0 kW per 100 grams of frozen gelled composite. However, Xiang’s teaching of the emission power (corresponding to the claimed input energy) of the microwave being controllable to ensure the drying effect of material suggests the input energy being based at least in part on the weight of the material. Thus, the claimed range of 0.5-2.0 kW per 100 grams of frozen gelled composite is obviously affected by factors such as the weight of the frozen gelled composite. It would have been obvious to one of ordinary skill in the art at the time of filing to optimize the input energy based on the weight of the frozen gelled composite by routine experimentation, thereby arriving at the claimed range of 0.5-2.0 kW per 100 grams of frozen gelled composite. "[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." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). See MPEP 2144.05.
The step e) reads on the claimed “curing the aerogel composite”.
Sachithanadam teaches that a curing step can advantageously ensure that the silica aerogel composite is substantially or completely dehydrated to ensure that the crosslinking agent is substantially or completely reacted with the elements; and the temperature and duration of the cure depends on the type and amount of crosslinking agent used, as well as the size and thickness of the silica aerogel composite [P12L33-P13L6]. This reads on the recited “to thereby ensure that the aerogel composite is at least substantially dehydrated and that the crosslinking agent is at least substantially reacted with other elements of the emulsion, the curing being performed at a temperature and duration based at least in part on the crosslinking agent used and size and thickness of the aerogel composite”.
Sachithanadam does not teach a bulk drying process. In the same field of endeavor, Xu teaches freezing and drying to remove water to obtain bulk drying of titanium dioxide/silicondioxide composite aerogel precursor [abstract]. It would have been obvious to one of ordinary skill in the art at the time of filing to induce bulk-drying in Sachithanadam’s method because Xu expressively teaches that bulk-drying with freeze-drying is suitable for making a silica aerogel. Sachithanadam in view of Xiang teaches microwave vacuum freeze drying as stated above. Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to configure the microwave vacuum freeze drying to induce bulk drying of the gelled composite.
Xiang teaches microwave vacuum freeze drying of hydrogel at vacuum pressure of about 10-30 Pa [p. 8, lines 12-14]; and when the vacuum pressure does not change in a certain time indicating that the hydrogel is completely dry, the vacuum is released [p. 8, lines 35-38]. It would have been obvious to one of ordinary skill in the art at the time of filing to conduct the microwave assisted vacuum freeze drying according to Xiang’s teaching because this has various advantages of avoiding long drying cycle, large energy consumption, or uneven heating, as stated above. This teaching reads on the claimed limitation of “the microwave assisted vacuum freeze-drying is configured to be performed at a pressure below about 200 Pa and to stop when the pressure drops below 50 Pa to induce bulk drying of the gelled composite”.
Regarding claim 9, Sachithanadam teaches that the composition comprises inorganic fillers, fire retardant [P21L24], strengthening agent [P21L11], and surfactant [P7L26].
Regarding claim 10, Xiang teaches that the microwave vacuum freeze drying device comprises a vacuum freezing-drying chamber [P3,last para.], which reads on the claimed microwave assisted vacuum freeze dryer.
Regarding claim 11, Sachithanadam teaches sol-gel technique [P1L15-16].
Regarding claim 12, Sachithanadam teaches that a further coating step is performed by coating the silica aerogel composite with a hydrophobic material, for example a silane coupling agent [P16L22-25].
Regarding claim 18, Xiang teaches starting the microwave vacuum freeze drying of hydrogel at -45 °C until the hydrogel is completely dry [p. 8 line 2]. The temperature of -45 °C is merely close to the claimed -50 °C; and a moisture content of below 0.5% is expected when the hydrogel is completely dry. One of ordinary skill in the art understands that the drying result depends on the drying temperature, pressure, and time. It would have been obvious to one of ordinary skill in the art at the time of filing to optimize the drying temperature, pressure, and time by routine experimentation, thereby arriving at the claimed -50 °C and 6-10 hours. See MPEP 2144.05.II.
Regarding claim 19, Schithanadam teaches curing the composite at about 60 °C to about 100 °C for about 2 hours to about 6 hours [p. 13, lines 4-11].
Regarding claim 20, Schithanadam teaches that the aerogel composite maintains the same mass as raw materials in the aerogel composite [p. 32, lines 27-28].
Regarding claim 21, Schithanadam teaches that the aerogel composite has a thickness of about 5 mm to about 30 mm [p. 27, lines 20-21].
Regarding claim 22, the limitations are addressed in the rejections of claims 8 and 18 above.
Regarding claim 23, the limitation is addressed in the rejection of claim 8 above.
Regarding claim 24, the limitation is addressed in the rejection of claim 19 above.
Regarding claim 25, the limitation is addressed in the rejection of claim 20 above.
Regarding claim 26, the limitation is addressed in the rejection of claim 21 above.
Regarding claim 27, Schithanadam teaches that the microwave assisted vacuum freeze-drying is configured for large scale production [p. 27. line 20]. The rest of the limitation is addressed in the rejections of claims 8 and 22 above.
Regarding claim 28, the limitation is addressed in the rejection of claim 8 above.
Regarding claim 29, the limitation is addressed in the rejection of claim 18 above.
Regarding claim 30, the limitation is addressed in the rejection of claim 19 above.
Regarding claim 31, the limitation is addressed in the rejection of claim 20 above.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JIANGTIAN XU whose telephone number is (571)270-1621. The examiner can normally be reached Monday-Thursday.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Robert Jones can be reached on (571) 270-7733. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JIANGTIAN XU/Primary Examiner, Art Unit 1762
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