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 .
The amendment filed 12/23/2025 has been entered. Claims 1-17 and 31-33 have been canceled. Claims 18-30 are pending in the application. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim Rejections - 35 USC § 112(a)
Claims 18-30 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the enablement requirement for generally the reasons recited in the prior office action and restated below with respect to the amended claims.
The claim(s) contains subject matter which was not described in the specification in such a way as to enable one skilled in the art to which it pertains, or with which it is most nearly connected, to make and/or use the invention. Amended claim 18 recites, “An optical solar reflector, comprising: a substrate; and a multilayer coating for thermal control of a surface of the substrate, the multilayer coating including a first inner layer deposited on the surface, a second intermediate layer applied on the first layer, and a third outer layer applied on the second intermediate layer, wherein: the first inner layer includes a co-dispersion of conductive nanoparticles and dielectric nanoparticles, wherein a volume fraction of conductive nanoparticles increases along a thickness of the first inner layer moving away from the second intermediate layer, and wherein the first inner layer has a hemispherical emissivity between 0.5 and 0.8”; however, the Examiner maintains that the instant disclosure fails to describe the claimed invention in such a way to enable one skilled in the art to which it pertains, or with which it is most nearly connected, to make the claimed invention such that an inner layer including a co-dispersion of conductive nanoparticles and dielectric nanoparticles with a volume fraction of the conductive nanoparticles provided in a gradient manner as instantly claimed has a hemispherical emissivity between 0.5 and 0.8 as instantly claimed without conducting undue experimentation, particularly given the lack of clarity thereof as discussed in detail below.
In determining whether the specification meets the enablement requirement, the Examiner again considered the following factors as set forth in In re Wands: (A) The breadth of the claims; (B) The nature of the invention; (C) The state of the prior art; (D) The level of one of ordinary skill; (E) The level of predictability in the art; (F) The amount of direction provided by the inventor; (G) The existence of working examples; and (H) The quantity of experimentation needed to make or use the invention based on the content of the disclosure. First, it is noted that the claimed invention is broadly directed to an optical solar reflector comprising a generic substrate and a multilayer coating that is defined not by the specific materials forming the layers thereof but by structural, electrical, thermal, and/or optical properties of the layers (e.g. “co-dispersion” of “nanoparticles”, “conductive”, “dielectric”, “extinction coefficient”, “high refractive index”, “low refractive index”, “resistivity”, etc.), and given that such properties may be exhibited by an endless combination of materials (as evidenced by the dependent claims), the breadth of the claims is extremely wide. Next, in terms of the nature of the invention and the state of the prior art, reference is again made to Iacovangelo (USPN 6,587,263) which is specifically directed to coated substrates for use as optical solar reflectors for a variety of applications, including space applications (e.g. a similar application or end use of the claimed “product” as discussed in the instant specification), wherein the substrate is provided with a multilayer coating of selected layer materials, thicknesses, and optical properties to provide desired optical and performance properties; and similarly, Brooks (USPN 8,665,175) which is directed to a thermal control film for spacecraft wherein the thermal control film comprises a multilayer interference filter of alternating higher and lower refractive index layers adapted to exhibit high reflectivity to solar radiation, low absorptivity across the microwave spectrum, and high emissivity in the far infra-red. With respect to emissivity and radiative cooling, the Examiner refers to the teachings of Yang (US2019/0086164A1) and Yu (US2018/0180331A1), both of which discuss radiative cooling utilizing a thermally or selectively emissive composite layer comprising one or more (nano)particles dispersed in a polymer matrix; while Chen (Synthesis, characterization and infrared emissivity study of polyurethane/TiO2 nanocomposites) and He (High emissivity coatings for high temperature application: Progress and prospect) discuss the effect(s) of synergistic interactions of composite constituents on emittance properties of the composite material (and the unpredictability thereof), with He broadly discussing the prospect of utilizing variable emittance coatings as spacecraft radiators for thermal control. Reference is also made to the Wikipedia.org article entitled “Emissivity” for a general overview of emissivity including hemispherical emissivity, practical applications where emissivity is important, and related optical properties, wherein the article notes that nanoparticles (i.e. wavelength- and subwavelength-scale particles), metamaterials, and other nanostructures may have emissivity properties that are not typical of most materials or objects, e.g. an emissivity greater than 1.
Further reference is made to Jaworske (Cermet coatings for solar Stirling space power), Cao (A review of cermet-based spectrally selective solar absorbers), Neto (Chromium silica co-sputtered graded Cermet for solar thermal collectors), and Esposito (Fabrication and optimisation of highly efficient cermet-based spectrally selective coatings for high operating temperature), each of which is broadly directed to cermet materials (i.e., composite materials comprising ceramic components and metal composites) and provide evidence that not only shows that such cermet materials, including those formed from the same materials as recited in the instant claims with respect to the “first inner layer” typically have low emissivity values, particularly values that are much lower than the claimed lower endpoint of 0.5, but also shows that emissivity of a given cermet combination is dependent not only upon the ratio of the selected metal and ceramic materials but also upon the measurement temperature, the substrate material, and the surface roughness of the layer and thus also dependent upon the surface roughness of the substrate and the method of forming said cermet, with Jaworske specifically disclosing cermets comprising Al, Ni, Ti, Pt, Cu and Mo as the metal component with Al2O3 as the ceramic component (Entire document); Cao disclosing a summary of a variety of different cermet materials including cermets formed from specific metals and ceramics/dielectrics as in the instant invention, by various methods, and having low thermal emittance values as well as discussing studies that investigated the influence of substrate choice and film thickness on spectral selectivity (Entire document, particularly Sections 2-3); Neto disclosing chromium silica co-sputtered graded cermets for solar thermal collectors provided on different substrates wherein the films deposited on stainless steel substrates presented higher absorptivity and lower emissivity values than the films on copper substrates (Entire document); and Esposito disclosing cermets formed of Mo and SiO2, particularly a multilayer structure including a low metal volume fraction cermet provided over a high metal volume fraction cermet providing improved performance over a graded cermet profile, that is dependent on the filling factor as well as temperature, and specifically noting that in spite of efforts of the scientific community to find a model able to predict the optical properties of cermets, available theoretical models fail in the estimation of the optical constants of cermet layers such that an appropriate optimization study has to utilize experimentally estimated optical data (Entire document, particularly Sections 1 and 3-4).
The cited prior art references are also representative of the level of one of ordinary skill in the art wherein as evidenced by the references, one skilled in the art would be capable of measuring optical properties such as emissivity or hemispherical emissivity of the surface of a layer, composite, or laminate utilizing known techniques, however, one of ordinary skill in the art would clearly recognize the amount of undue experimentation needed to “reverse engineer” the claimed “first inner layer [that] includes a co-dispersion of conductive nanoparticles and dielectric nanoparticles, wherein a volume fraction of conductive nanoparticles increases along a thickness of the first inner layer moving away from the second intermediate layer, and wherein the first inner layer has a hemispherical emissivity between 0.5 and 0.8” as recited in instant claim 1, in order to determine what combination of “conductive” nanoparticles, “dielectric” nanoparticles, and matrix material if any, as well as nanoparticle size(s), nanoparticle morphology (e.g. shape, crystal structure, clustering, etc.) and nanoparticle concentrations including the claimed graded volume content of “conductive” nanoparticles would provide a hemispherical emissivity in the claimed range of between 0.5 and 0.8.
In looking at the amount of direction provided by the Applicant, it is noted that not only are there no working examples nor hypothetical examples in the specification, but also the specification provides no indication or guidance as to how one could determine what parameters to modify or even could be modified with respect to the inner layer in order to meet the property limitations of the claimed invention or produce “inventive” examples in comparison to comparative examples falling outside of the claimed limitations. Hence, the Examiner again takes the position that the Applicant fails to provide sufficient guidance to one having ordinary skill in the art as to how to select from an almost limitless combination of “conductive” nanoparticles, “dielectric” nanoparticles, and other co-dispersion constituents to make the claimed optical solar reflector without performing undue experimentation, particularly given the level of unpredictability in the art with respect to nanocomposite/cermet materials.
Claim Rejections - 35 USC § 112(b)
Claims 18-30 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. As discussed in the prior office action, Claim 18 recites, “the first inner layer includes a co-deposition of conductive nanoparticles and dielectric nanoparticles,” however, given that the claim nor the specification clearly recites that the “conductive” nanoparticles are electrically conductive nanoparticles (or what type of conductivity is meant by the “conductive” limitation), it is unclear whether the “conductive” nanoparticles refer to nanoparticles that are electrically conductive, thermally conductive, ionically conductive, etc., especially given that the claim recites that the multilayer coating is for “thermal control” (emphasis added) and the specification recites that the invention “relates generally to a multilayer coating with thermo-optical properties” (emphasis added). Additionally, given the materials listed for the claimed “conductive” nanoparticles in the specification and claims 19 and 21, such as aluminum suboxide (AlxO) which although thermally conductive is not typically considered an electrically conductive material except under high pressures, as well as the materials listed for the claimed “dielectric” nanoparticles in the specification and claim 20 such as “Al” (i.e. aluminum) which is a metal and is not a “dielectric” material in the art (and is actually recited in claim 19 as a material for the “conductive” nanoparticles), the Examiner maintains her position that it is unclear as to what is meant to be encompassed by the relative terms “conductive” nanoparticles and “dielectric” nanoparticles, especially given Applicant’s exemplified materials and that many dielectric nanoparticles are also thermally conductive.
The dependent claims do not remedy the above, and hence are indefinite for the same reasons as above.
Dependent claims 27-28 are (further) 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. Claim 27 recites, “wherein the layer of the dielectric material transparent in the visible with the high refractive index in the visible has a refractive index in the visible between 1.6 and 2.5” (emphasis added, on lines 1-3); while claim 28 recites, “wherein the layer of the dielectric material transparent in the visible with the low refractive index in the visible has a refractive index in the visible between 1.2 and 1.7” (emphasis added, on lines 1-3); however given that claim 18, from which claims 27-28 depend, has been amended to recite “a dielectric material having an extinction coefficient in the visible spectrum of less than 1x10-3” (in place of “transparent in the visible”), the above limitations in bold lack clear antecedent basis.
Claim Rejections - 35 USC § 112(d)
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claims 27 and 28 are rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends. Claim 27 recites, “wherein the layer of the dielectric material transparent in the visible with the high refractive index in the visible has a refractive index in the visible between 1.6 and 2.5” (on lines 1-3); while claim 28 recites, wherein the layer of the dielectric material transparent in the visible with the low refractive index in the visible has a refractive index in the visible between 1.2 and 1.7” (on lines 1-3); however given that both claims 27-28 depend upon claim 18 which has been amended to recite a high refractive index in the visible of between 1.6 and 2.5 and a low refractive index in the visible of between 1.2 and 1.7, claims 27-28 do not further limit claim 18. Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Response to Arguments
Applicant's arguments filed 12/23/2025 have been fully considered but they are not persuasive with respect to the rejections under 35 U.S.C. 112(a) and 112(b), and although the Examiner does not concede to Applicant’s arguments with respect to the obviousness rejection over Suzuki as presented in the prior office action, given the lack of enablement and more particularly, the lack of clarity of the instant claims, the prior art rejection has been withdrawn by the Examiner at this time but may be reconsidered upon submission of claim amendments to address the above 112 rejections. More specifically, with respect to the enablement rejection under 35 U.S.C. 112(a), the Applicant notes that claim 1 was amended to be directed to “an optical solar reflector” and that the plurality of layers that includes at least one layer of dielectric material of high refractive index and at least one layer of dielectric material of low refractive index were amended to clarify the definitions of “transparent in the visible”, “low refractive index”, and “high refractive index”. The Applicant then states, “Regarding the first inner layer, the description specifies that this material is commonly known in the art as CERMET (see the description on page 5) and it provides a sufficient number of examples of materials suitable for producing such a layer. Moreover, page 6 details that this material can be obtained through reactive sputtering from a single source by gradually changing the oxidation state of the material during deposition or, as an alternative, the layer is produced by co-deposition of different materials from two or more distinct sources” (emphasis added), wherein “[i]n view of the foregoing, Applicant believes claim 1 is enabled, and respectfully requests” withdrawal of the 112(a) rejection (see page 7 of the response). However, the Examiner respectfully disagrees and notes that even if the claims were directed to an optical solar reflector wherein the first inner layer was limited to CERMET materials, which the Examiner notes the claims are not, or even limited to the list of “conductive nanoparticles” as in instant claim 19 with the list of “dielectric nanoparticles” as in instant claim 20, which the claims are not, or even more specifically to the combination of “dielectric nanoparticles” made of Al2O3 with “conductive nanoparticles” made of AlxO or Al as recited in instant claim 21, the Examiner maintains her position that the Applicant fails to provide sufficient guidance as to how to produce a layer that “includes a co-dispersion of conductive nanoparticles and dielectric nanoparticles” in order to obtain a hemispherical emissivity between 0.5 and 0.8 as instantly claimed without conducting undue experimentation, especially given that even cermets, as argued by the Applicant, comprising a combination of ceramic/dielectric and metal components as recited by the Applicant are known to provide much lower emissivity values, and are dependent upon various parameters other than just the materials and contents thereof including the substrate and process by which they are formed. Further, given that the Applicant provides no working or theoretical examples nor any guidance as to how to control the hemispherical emissivity of the layer in order to fall within the claimed range, and given the level of unpredictability with respect to optical properties of a “co-dispersion of conductive nanoparticles and dielectric nanoparticles” or of a cermet material, Applicant’s claim amendments and arguments are not persuasive to overcome the rejection under 35 U.S.C. 112(a).
With respect to the rejection under 35 U.S.C. 112(b) as maintained above given the claimed relative “conductive” and “dielectric” limitations, the Applicant argues that “[r]egarding the definition of ‘conductive particles’ and ‘dielectric particles’, these terms should be interpreted according to their common technical meaning in the field of functional coating materials” (emphasis added) and that “[i]n CERMETs, conductive particles are typically metal particles (e.g., aluminum, nickel, silver, copper, molybdenum, titanium, tungsten, etc.) or conductive oxides (such as ITO, TiN, AZO) dispersed in the ceramic matrix” (emphasis added) while “[d]ielectric particles, on the other hand, are insulating ceramic materials, such as oxides (Al2O3, SiO2, ZrO2, TiO2, etc.), nitrides, or carbides” that “constitute the matrix or continuous phase of CERMET providing the material with electrical insulation properties, mechanical strength, chemical stability, and if necessary, optical transparency” (see Section E on page 8). However, the Examiner first notes that the instant invention is not limited to CERMETs, and although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims; and hence, although CERMETs by definition include ceramic components and metal components wherein ceramics are typically dielectric and metals are conductive, whether thermally and/or electrically, not all co-dispersions are CERMETs given that the two types of nanoparticles may be co-dispersed in a polymeric matrix, and not all dielectrics are ceramics nor are all “conductive” materials metals. It is also noted that the “common technical” meaning “in the field of functional coating materials” of “conductive nanoparticles” is not limited to metals or “conductive” oxides such as ITO and AZO as argued by the Applicant, and in fact, includes various non-metals and/or electrically insulative or “dielectric” materials that may provide thermal conductivity to functional coating materials and/or optical articles as evidenced by Strader (US2020/0287253A, Entire document, particularly Paragraph 0025, 0028, 0032, 0048-0049, 0059); or Akarsu (US2010/0291374A1, Paragraph 0035); or Williams (US2015/0362762A1, Paragraph 0045), particularly given that the specification and instant claims do not limit the claimed “conductive” nanoparticles to “electrically conductive” nanoparticles. Further, it is noted that the Applicant specifically recites that conducive particles are metal particles with examples thereof including aluminum, and although aluminum is recited in instant claim 19 with respect to the “conductive” nanoparticles, aluminum, i.e., “Al”, is also recited in instant claim 20 with respect to the “dielectric” nanoparticles, and given that Al/aluminum would NOT be considered a “dielectric” material in “the field of functional coating materials” or any other field for that matter, Applicant’s arguments are not persuasive.
Any objection or rejection from the prior office action not restated below has been withdrawn by the Examiner in light of Applicant’s claim amendments and arguments filed 12/23/2025.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Zhao (CN102501461A, machine translation also attached) discloses a high heat-absorbing coated substrate comprising in order, a substrate (1), a reflective layer (2), an absorbing layer (3), and an antireflection layer (4), wherein the absorbing layer (3) is a M-Al2O3 metal-ceramic layer comprising particles of metal M dispersed in a dielectric Al2O3 matrix in a volume fraction that gradually decreases from an inner surface towards an outer surface.
THIS ACTION IS MADE FINAL. 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 MONIQUE R JACKSON whose telephone number is (571)272-1508. The examiner can normally be reached Mondays-Thursdays from 10:00AM-5:00PM.
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/MONIQUE R JACKSON/Primary Examiner, Art Unit 1787
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