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 11/24/2025 has been entered. Claims 6-7 and 11-12 have been canceled. Claims 1-5, 8-10, and 13-17 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
Claims 1-5, 8-10, and 13-17 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 written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. Claim 1 has been amended to recite, “each of the particles including an electrically conductive platelet of doped metal oxide with an empty internal cavity and having a coating on the platelet and without a core or carrier substrate” (emphasis added), however, the original disclosure at the time of the invention fails to provide support for the claimed limitation.
Claim Rejections - 35 USC § 103
Claims 1-5, 8-10, and 13-17 are rejected under 35 U.S.C. 103 as being unpatentable over Klaussner (WO2015/128367, please refer to US2016/0374237 as an English language translation of the WO document), as evidenced by Song, and in view of Kutsovsky (US2006/0067868) or Archer (US2010/0258759) for generally the reasons of record as recited in the office action dated 8/26/2025, and restated below with respect to the amended claims, wherein the Examiner again notes that Kutsovsky clearly teaches that the produced metal oxide shell particles (which include an “empty internal cavity”) can be subjected to chemical modification using means common in the art such as by reaction with silane compounds, particularly alkoxysilane as discussed in Paragraph 0063 reading upon the claimed “having a coating on the platelet…the coating on the platelet comprising one or more silanes, waterglass and/or an undoped metal oxide” as in instant claim 1, while Archer teaches that the metal oxide hollow or shell particles comprising an internal void or inner hollow cavity (“empty internal cavity”) can comprise a plurality of metal oxide shells or two or more nanostructured metal oxide shells surrounding the inner cavity, e.g., a second metal oxide shell as a “coating” on a first metal oxide shell, wherein the metal oxide shells can be mixed metal oxides (e.g., “doped metal oxide”), and/or the resulting nanostructured metal oxide shells can also be coated with additional industrially useful materials based upon the desired end use (Paragraphs 0008, 0020, and 0050-0053; also reading upon the claimed “having a coating on the platelet…the coating on the platelet comprising one or more silanes, waterglass and/or an undoped metal oxide” as in instant claim 1), such as for providing electrical conductivity properties although the optionally, the metal oxide nanostructures themselves can bear electrical conductivity properties; and hence, the Examiner maintains her position that the claimed invention would have been obvious over the teachings of Klaussner, as evidenced by Song, and in view of Kutsovsky or Archer as discussed in detail below.
As discussed in prior office actions, Klaussner teaches “a corona shielding system for an electric machine, comprising a filler in a polymeric matrix [as in instant claim 2], the filler comprising both planar and spherical/globular [“globe”] particles that are resistant to partial discharges and electrically conductive” (Paragraph 0013), wherein “the electrical conductivity, which is good in the presence of only planar particles in two spatial directions but is very poor in the third, can be adjusted anisotropically in a targeted manner” by adjusting the amount of spherical or globe particles added to the planar platelet-like particles that are known to align during the production process such that the platelet-like particles create conductivity paths in the two spatial or orthogonal directions, along which the conductivity is high, however the conductivity in the perpendicular or third orthogonal direction is quite low (Entire document, particularly Abstract, Paragraphs 0020-0023). Klaussner teaches that the platelet-like particles comprise a doped metal oxide, and may comprise a core, preferably a lightweight core or carrier substrate such as mica, silica, alumina or glass platelets, upon which the doped metal oxide is provided as a coating layer or “shell” surrounding the core or carrier substrate, wherein the metal oxide is selected from tin oxide, zinc oxide, zinc stannate, titanium dioxide, lead oxide or non-oxidic silicon carbide (as in instant claims 3 and 8), that can be doped with preferably antimony, indium or cadmium (as in instant claims 9 and 10) in order to set the conductivity thereof by the doping (as in instant claim 1; Paragraphs 0018 and 0026-0028).
Klaussner teaches that the particle mass concentration of the particles in the carrier matrix may be chosen such that the corona shielding material is above the percolation threshold, preferably above 15% by weight (as in instant claims 1 and 15; Paragraph 0019), wherein the tailored addition of the spherical or globe particles (as in instant claim 16) increases the electrical conductivity perpendicularly in relation to the directed/aligned filler platelets such that the anisotropic electrical resistance of the corona layer can be adapted or set within certain ranges and the percolation thresholds of the three spatial directions shift to much lower filler concentrations (Paragraphs 0023-0025). Klaussner teaches that the spherical or globe particles may also be produced from doped metal oxide wherein the general conductivity of such spherical or globe particles can be set by the doping of the metal oxide, as with the planar fillers, with an example ratio of planar particles to spherical particles being approximately 3:1 (Paragraphs 0024 and 0027; thus a content of planar particles overlapping the claimed range given the overall particle mass concentration of preferably about 15% by weight as noted above).
Hence, with respect to the claimed invention as recited in instant claims 1-3, 8-10, 15, and 16, Klaussner teaches a resistance coating comprising an electrically insulating polymeric matrix as in instant claim 2; electrically conductive particles incorporated therein in a content as in instant claim 15, wherein the electrically conductive particles comprise metal oxides as in instant claims 3 and 8-9, include platelet and globe particles as in instant claim 16, and have a conductivity generated by doping metal oxide with a doping element such as antimony, indium or cadmium as in instant claim 10; wherein a percolation threshold of the resistance coating is exceeded in two orthogonal directions and conductivity of the resistance coating is higher in the two directions than a third orthogonal direction as in instant claim 1; and wherein the particles include an aligned flake structure in a plane perpendicular to the third orthogonal direction as in instant claim 1 (e.g. providing an increased discharge resistance in the third orthogonal direction); but does not teach that each of the electrically conductive planar/platelet particles containing the doped metal oxide comprises an electrically conductive platelet of doped metal oxide with an empty internal cavity and having a coating on the platelet and without a core or carrier substrate, wherein the coating on the platelet comprises one or more silanes, waterglass, and/or undoped metal oxide as recited in instant claim 1, nor that the conductivity of the resistance coating in the two orthogonal or spatial directions is higher by at least a factor of 10 as instantly claimed.
However, it is first noted as discussed in detail in prior office actions, that it is well established in the art that conductive coatings or composites formed from flakes or platelets in a manner that they align to form laminar structures within a resin matrix thereby producing an anisotropic composite or a composite having 2-D isotropy with the electrical conductivity being greater in all planar directions than in the thickness direction (“third orthogonal direction”) can be provided such that the in-plane conductivity (two orthogonal directions) is orders of magnitude higher than the thickness direction as evidenced by Song (Paragraph 0070), and although Song teaches the use of expanded graphite as the flakes or platelets, it would have been obvious to one having ordinary skill in the art before the effective filing date of the instant invention to clearly recognize that the same or similar anisotropy or 2-D isotropy as in Song could be obtained in the invention taught by Klaussner based upon the desired conductivity properties for a particular end use of the resistance coating as taught by Klaussner, particularly given that both Klaussner and Song provide a clear teaching and/or suggestion that the type of conductive filler(s) or flake(s) as well as the content directly affect the conductivity properties of the coating.
Further, although Klaussner teaches that the electrically conductive planar particles “may comprise a core” (Paragraph 0014), preferably mica, silica flour, alumina or glass platelets (Paragraph 0017) which are then coated with a conductive coating of the doped metal oxide (Paragraph 0018), e.g. thereby forming a doped metal oxide conductive “shell” surrounding the “core” platelets as a solid support, Klaussner does not teach that the doped metal oxide coated platelets are provided with an “empty internal cavity” and having a coating on the platelet and without a core or carrier substrate. However, as previously discussed, Kutsovsky teaches metal oxide shell particles, typically in platelet shape, that are obtained by removing a removable template support upon which the metal oxide is coated, e.g. removing the “core” of the core-shell particle, thereby resulting in planar or unique shaped metal oxide shell particles or platelets surrounding an internal cavity which can improve certain properties, such as over spherical particles, can be altered to achieve various morphology and shapes desired for a particular applications, and may better enhance the composition that the particles are used in (Entire document, particularly Abstract; Paragraphs 0002-0004, 0007-0008, 0017-0018, 0029 and 0059); wherein the Examiner notes that one skilled in the art would clearly recognize that removal of the template to form the internal cavity would provide an “empty” internal cavity as in the claimed invention. Kutsovsky teaches that although the invention is described in detail with regards to silica, the invention also relates to metals and metal oxides other than silica, including metals or oxides thereof as recited in Paragraphs 0052-0053 such as zinc, titanium, tin, antimony, and lead (e.g. metals recited by Klaussner for use in the doped metal oxide particles); wherein combinations of metal-containing species or compounds as starting materials may also be utilized to produce mixed oxides or multi-stage phases containing two or more different metals or metal oxides, thus clearly suggesting “doped” metal oxides as in instant claim 1, mixed metal oxides as in instant claim 3, (poly)crystalline materials as in instant claims 4-5, metal oxides as in instant claim 8, antimony-doped as in instant claims 9-10, as well as additional undoped metal oxide in the coating as in instant claim 1 given the “multi-stage” phases; Entire document, particularly Paragraphs 0017, 0041-0047, and 0050-0053).
Kutsovsky also teaches that the produced metal or metal oxide particles of the invention can be subjected to chemical modification using means common in the art such as by reaction with the silane compounds as disclosed in Paragraph 0063 including an alkoxysilane as further described in the patents incorporated by reference in Paragraph 0063, and given that one having ordinary skill in the art would readily understand that an alkoxysilane chemical modification may produce a silane-containing or “undoped metal oxide”-containing coating on the surface to be treated (e.g. as evidenced by Tan, USPN 6,548,264, Col. 10, lines 35-48; or Mulvaney, USPN 6,548,168, Abstract, Fig. 1, Cols. 5-6, and Examples), Kutsovsky provides a clear teaching and/or suggestion of a coating on the surface of the doped metal oxide shells or platelets wherein the coating comprises “one or more silanes…and/or an undoped metal oxide” as instantly claimed. Kutsovsky teaches that a very inexpensive final product can be produced given that a very inexpensive feedstock can be utilized as the removable template support when minor impurities do not affect the overall user application, and teaches that the resulting metal or oxide thereof can be processed in any conventional manner in which metal oxide products are processed, and can be utilized in any conventional application or in a variety of formulations or compositions for numerous uses as disclosed in Paragraphs 0064-0066, in the same manner and same amounts as used conventionally, including as fillers or reinforcing agents, in a polymer matrix (e.g. as in Klaussner) where they can form a barrier through the filled matrix, for the formation of capacitor components, in polymers, inks and coatings, etc. (Paragraphs 0003, 0057, 0061, 0064-0066).
Similarly, Archer teaches nanostructured metal oxides containing internal voids (e.g., “empty internal cavity”), such as nanorods, nanotubes, nanodisks (e.g. platelet shape), among other nanostructures, and a method of producing the nanostructured metal oxides, particularly polycrystalline metal oxides such as tin oxides, wherein the method may be a template method or template-free method and provides an inexpensive, high-yield method for mass production of hollow metal oxide nanostructures that can have shell(s) and/or wall(s) (i.e. without a core or carrier substrate) with an internal space, cavity, or void, and compositions that are easily controlled and tailored to provide desired properties for a particular end use including desired electrical conductivity or other electrical properties (Entire document, particularly Abstract; Paragraphs 0008, 0020-0026, 0028-0029, 0033, and 0049-0051). Archer teaches that in addition to tin oxides, the nanostructures may also comprise oxides of titanium, indium, zinc or other metals as disclosed in Paragraph 0008 and combinations thereof (similar to the teachings of Klaussner and Kutsovsky, and reading upon the claimed “doped metal oxide”), can comprise a plurality of shells (reading broadly upon a coating comprising an undoped metal oxide as in instant claim 1), can be doped with metals, and/or the generated hollow particles may also be coated with additional industrially useful materials based upon the desired end use, wherein the metal oxide nanostructures can bear electrical conductivity properties (as in Klaussner) and can be used in a variety of applications (Paragraphs 0008 and 0050-0053).
Thus, given that each of Kutsovsky and Archer clearly teaches advantages of utilizing particles without a core or carrier substrate in comparison to core-shell particles comprising a core or carrier substrate as in Klaussner, it would have been obvious to one having ordinary skill in the art before the effective filing date of the instantly claimed invention to utilize the coated, doped metal oxide platelet shell particles as taught by Kutsovsky or Archer which comprise doped metal oxide platelets with an empty internal cavity and without a core or carrier substrate as in the claimed invention and provided on an exterior surface thereof with a silane and/or undoped metal oxide as taught by Kutsovsky or Archer, as the coated, doped metal oxide platelet particles in the invention taught by Klaussner and/or to provide the coated, conductive doped metal oxide platelet particles of the invention taught by Klaussner in the form of coated platelet particles with an internal void or “empty internal cavity” and without a core or carrier substrate, i.e. by removing the “core” of the coated platelet particles of Klaussner, and determining the optimum doped metal oxide composition(s) to provide the desired conductivity for a particular end use, given that it is prima facie obviousness to simply substitute one known element for another to obtain predictable results and/or in light of the reduced cost and ease in controlling the shape and composition of the metal oxide shells as taught by Kutsovsky or Archer, prima facie obviousness to combine prior art reference teachings to arrive at the claimed invention where there is some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference. Therefore, the claimed invention as recited in instant claims 1-3, 8-10, 15, and 16 would have been obvious over the teachings of Klaussner, as evidenced by Song, and in view of Kutsovsky or Archer.
Further with respect to instant claim 3 as well as claims 4-5 and 17, it is again noted that Klaussner broadly teaches that the doped metal oxide may comprise metal oxides selected from tin oxide (as in instant claim 8), zinc oxide, zinc stannate (as in instant claim 3), titanium oxide, and lead oxide, with the doping element selected from antimony, indium and cadmium (as in instant claims 9-10), wherein the globe particles may also be selected from the same doped metal oxides, while each of Kutsovsky and Archer similarly teaches the above metals or metal oxides as well as mixtures thereof as discussed in detail above; and given that the selection of any of the recited metal oxides, metals and/or recited doping elements, and any combinations thereof, which include crystalline and/or polycrystalline materials as in instant claims 4-5 and 17, would have been obvious to one having ordinary skill in the art before the effective filing date of the instantly claimed invention, the claimed invention as recited in instant claims 3-5 and 17 would have been obvious over the teachings of Klaussner, as evidenced by Song, in view of Kutsovsky or Archer, given that it is prima facie obviousness to choose from a finite number of identified, predictable solutions, with a reasonable expectation of success, and/or prima facie obviousness to simply substitute one known element for another to obtain predictable results.
With respect to instant claims 13-15, Klaussner provides a clear teaching that the conductivity or resistance of the coating can be tailored based upon the metal oxide, doping and content of the platelets and globe filler in the coating wherein the particle mass content is above 15% by weight such that the coating is above the percolation threshold, and although Klaussner does not specifically teach the electrical resistance and nonlinearity of the resistance coating as instantly claimed, one having ordinary skill in the art before the effective filing date of the instantly claimed invention would have been motivated to utilize routine experimentation to determine the optimum metal oxide and doping composition, as well as particle content to provide the desired resistance and nonlinearity for a particular end use of the invention taught by Klaussner, as evidenced by Song, in view of Kutsovsky or Archer; and given that Klaussner teaches a similar end use as in the claimed invention, a resistance coating having electrical properties within the claimed ranges would have been obvious to one having ordinary skill in the art before the effective filing date of the instantly claimed invention thereby rendering the invention as recited in instant claims 13-15 obvious over Klaussner, as evidenced by Song, in view of Kutsovsky or Archer.
Response to Arguments
Applicant's arguments filed 11/24/2025 have been fully considered but they are not persuasive. The Applicant argues that the “cited references [allegedly] do not describe electrically conductive particles as claimed including a doped metal oxide with an empty internal cavity and having a coating on the platelet and without a core or carrier substrate”, arguing that Archer is cited as teaching a template-free method but that there is allegedly no teaching in Archer “suggesting that the particles described there in might be made of a doped metal oxide much less that they be amenable to a coating on the plated comprising one or more silanes, waterglass, and/or undoped metal oxide” (see page 6 of the response). The Applicant then states, “For at least these reasons, Independent Claim 1 is [allegedly] not rendered obvious by the cited references, whether considered alone or in combination” (see page 7 of the response). However, the Examiner respectfully disagrees and first notes that the obviousness rejection was based upon the teachings of Klaussner in view of Kutsovsky or Archer, and given that the Applicant provided no substantive arguments over Klaussner in view of Kutsovsky, the rejection of claims 1-5, 8-10, and 13-17 over the combination of Klaussner, as evidenced by Song, in view of Kutsovsky has been maintained by the Examiner.
In terms of Applicant’s arguments over Archer taken alone, the Examiner first notes that one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). In the instant case, with respect to the combined teachings of Klaussner (as evidenced by Song) in view of Archer, Klaussner already teaches doping of the metal oxide shell to provide desired electrical conductivity or to set the conductivity thereof by the doping, wherein Archer, like Kutsovsky, was relied upon for teaching the benefits of a hollow structure “without a core or carrier substrate” or nanostructure having “an empty internal cavity” or void and one or more shells surrounding the internal space of the cavity or void, wherein the nanostructures can be tailored to provide desired properties for a particular end use via methods that are easier to control and less costly than existing shell formation methods; and given the teachings of Archer that the nanostructure may comprise two or more metal oxide shells, Archer also teaches and/or suggests a coating of “undoped metal oxide” as in the claimed invention as discussed in detail above. Further, given that Archer specifically teaches that the shell(s) can be formed by various metal oxides including oxides as recited in Paragraphs 0008 and/or 0020 and “combinations thereof”, particularly tin oxides and “oxides of titanium, zirconium, boron, aluminum, germanium, indium, gallium, hafnium, silicon, vanadium, or tantalum, zinc, copper, iron, nickel, copper and combinations thereof”; that the resulting nanostructures can be further coated with additional industrially useful materials such as to provide electrical conductivity properties; and that the metal oxide nanostructures themselves can bear electrical conductivity properties as well, thus providing a reasonable expectation of success when combining the teachings of Archer with Klaussner, Applicant’s arguments again Archer taken alone are not persuasive.
Hence, the Examiner maintains her position that the claimed invention would have been obvious over the teachings of Klaussner, as evidenced by Song, and in view of Kutsovsky or Archer as discussed in detail above.
Any objection or rejection from the prior office action not restated above has been withdrawn by the Examiner in light of Applicant’s claim amendments and arguments filed 11/24/2025.
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