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 .
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.
Information Disclosure Statements
The Information Disclosure Statements filed on 22 May 2024 and 5 February 2026 have been received and considered by the Examiner.
Preliminary Amendment
Applicant’s preliminary amendments to the claims and specification filed on 22 May 2024 have been entered and considered for this action.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1 and 2 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Bushell et al. (Nanomaterials 2020, 10, 1812), and with respect to claim 2, as evidenced by Schutrum et al. (bioRxiv 2026.03.10.710632, DOI: 10.64898/2026.03.10.710632).
Regarding claim 1, Bushell discloses an alumina powder (Al-02) having a relative standard deviation of a volume-based crystallite diameter distribution of 0.54 (2.7nm SD / 5 nm size; Table 2) as determined by analyzing X-ray diffraction peaks by a fundamental parameter method (Section 2.2).
Regarding claim 2, Bushell discloses the alumina powder of claim 1, and further discloses that this powder has an average aspect ratio of 1.4. The roundness is the inverse of the aspect ratio, as evidenced by Schutrum (p. 4, line 97), and so these particles have an average roundness of 0.72.
Claim Rejections - 35 USC § 102/103
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 and 3 are rejected under 35 U.S.C. 102(a)(1) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Watanabe et al. (US 6,814,917 B1), as evidenced by Sumitomo (High Purity Alumina, Product Handbook, March 2024; retrieved from the Internet <URL: https://sumichem-at.com/wp-content/uploads/2024/04/HPA-ENG-MAR2024.pdf> on 31 August 2026).
Regarding claim 1, Watanabe discloses the same commercial alumina powder (AA-03 from Sumitomo Chemical; Example 4, col. 9) as presented in the instant specification (Sample 11, Comparative Example 5). The instant specification teaches that this material exhibits a relative standard deviation of a volume-based crystallite diameter distribution of 0.22 (Table 3), which lies just outside the instantly claimed range of 0.25-0.80.
Watanabe also teaches that the size distribution of the particles in the AA-03 material can be described by D90 (1.38 μm; col. 9, l. 34) and D10 (0.26 μm; col. 9, l. 34), which together give a width of the particle size distribution found in the material. From the D90 and D10 data disclosed by Watanabe, one can calculate a relative span, defined here as
D
90
-
D
10
D
50
, where the AA-03 material has a relative span of 3.4. Watanabe additionally teaches that the related material, AA-02, has smaller average size but a wider particle size distribution, as revealed by its larger relative span of 4.5 (calculated from the data in Example 3).
Watanabe does not specifically disclose a relative standard deviation of the volume-based crystallite diameter distribution.
However, Sumitomo provides evidence that the particles of their AA series alumina products are comprised of single crystals (p. 12), which supports that as particle size increases, so does crystallite size. Therefore, as the distribution of relative particle size distribution widens, so should the relative standard deviation of a volume-based crystallite diameter determined by analyzing X-ray diffraction peaks by a fundamental parameters method, as both are measures of the width of the particle/crystallite size distribution.
Because the particles of the AA-02 powder have a wider relative size distribution that the AA-03 powder, and because the AA-03 powders fall just below the range of relative standard deviation of a volume-based crystallite diameter imposed by the instant claim, it is reasonable to conclude that the AA-02 powders would have a relative standard deviation of a volume-based crystallite diameter that falls within the instant claim.
Alternatively, the particles of the AA-02 powder would have a relative standard deviation of a volume-based crystallite diameter in the range of 0.22-0.25, or else above 0.80. In either of these cases, it is noted that the courts have stated where the claimed ranges “overlap or lie inside the ranges disclosed by the prior art” and even when the claimed ranges and prior art ranges do not overlap but are close enough that one skilled in the art would have expected them to have similar properties, a prima facie case of obviousness exists (see In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990); Titanium Metals Corp. of America v. Banner, 778 F2d 775. 227 USPQ 773 (Fed. Cir. 1985) (see MPEP 2144.05.01). Therefore, the claimed ranges merely represent an obvious variant of the properties associated with the AA-02 and AA-03 powders in the cited prior art.
Once a reference teaching product appearing to be substantially identical is made the basis of a rejection, and the examiner presents evidence or reasoning to show inherency, the burden of proof shifts to the applicant. "[T]he PTO can require an applicant to prove that the prior art products do not necessarily or inherently possess the characteristics of [their] claimed product. Whether the rejection is based on inherency’ under 35 U.S.C. 102, on prima facie obviousness’ under 35 U.S.C. 103, jointly or alternatively, the burden of proof is the same, and its fairness is evidenced by the PTO’s inability to manufacture products or to obtain and compare prior art products." In re Best, 562 F.2d 1252, 1255, 195 USPQ 4380, 483-34 (CCPA 1977)), see MPEP 2112. Applicant has not clearly shown an unobvious difference between the instant invention and the prior art’s product.
Regarding claim 3, the particles of the AA-03 alumina powder have a volume average diameter of 1450 Å, as evidenced by the instant specification (Table 3). The particles of the AA-02 powder disclosed by Watanabe are about 50% smaller than those of the AA-03 powder (D50 of 0.20 μm vs. 0.33 μm; Examples 3 and 4), and because the particles are single crystals, are also expected to have a volume-based crystallite diameter similarly smaller, or approximately 900 Å, which falls within the instantly claimed range.
It is again noted that the PTO can require an applicant to prove that the prior art products do not necessarily or inherently possess the characteristics of [their] claimed product. Whether the rejection is based on inherency’ under 35 U.S.C. 102, on prima facie obviousness’ under 35 U.S.C. 103, jointly or alternatively, the burden of proof is the same, and its fairness is evidenced by the PTO’s inability to manufacture products or to obtain and compare prior art products." In re Best, 562 F.2d 1252, 1255, 195 USPQ 4380, 483-34 (CCPA 1977)), see MPEP 2112.
Claim Rejections - 35 USC § 103
Claim 2 is rejected under 35 U.S.C. 103 as unpatentable over Watanabe et al. (US 6,814,917 B1) as evidenced by (High Purity Alumina, Product Handbook, March 2024; retrieved from the Internet <URL: https://sumichem-at.com/wp-content/uploads/2024/04/HPA-ENG-MAR2024.pdf> on 31 August 2026).
Regarding claim 2, the AA-02 and AA-03 alumina powders disclosed by Watanabe anticipate or render obvious the alumina powder of claim 1, as analyzed above. It is further noted that the AA-03 powder has an average roundness of 0.87, as evidenced by the instant specification (Tables 2 and 3, Sample 11), which lies just outside the instantly claimed range of 0.71-0.86. The very similar AA-02 powders are expected to have similar roundness parameters.
It is again noted that the courts have stated where the claimed ranges overlap or lie inside the ranges disclosed by the prior art and even when the claimed ranges and prior art ranges do not overlap but are close enough that one skilled in the art would have expected them to have similar properties, a prima facie case of obviousness exists. Applicant has not shown a non-obvious difference between powders of a roundness of 0.87 and those with roundness of 0.86 that is commensurate in scope with the instant claim. Therefore, the claimed range merely represents an obvious variant and/or routine optimization of the powders in the cited prior art.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Nicholas A Piro whose telephone number is (571)272-6344. The examiner can normally be reached Mon-Fri, 8:00 am-5:00 pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sally Merkling can be reached at (571) 272-6297. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/NICHOLAS A. PIRO/Assistant Examiner, Art Unit 1738
/PAUL A WARTALOWICZ/Primary Examiner, Art Unit 1735
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