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 .
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 1, 2, 4-19, 21 and 22 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.
Claims 1, 7 and 10 claim “a grain-preferred orientation (511).” This term “grain-preferred” is not used in the specification and “preferred” is not clear as to what such grain orientation is preferred compared to. The specification does not clarify what is considered spinel structure that a preferred grain/crystal orientation versus a spinel structure that has no preferred orientation because the specification refers to Fig. 7 as showing structure with a preferred crystal orientation while refers to Fig. 9 as structure with no preferred crystal orientation. In each Figure, there is an orientation that has the largest peak among numerous peaks, (511) in Fig. 7 and (311) in Fig. 9, yet it appears only one of the Figures is considered as showing a preferred crystal orientation. Thus the phrase “a grain-preferred orientation (511)” is not clear if in reference to the largest peak of an XRD of the spinel structure or any one of the largest peaks relative to all the peaks for the spinel structure.
Claim Rejections - 35 USC § 102
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(s) 1, 2 and 4-9 are rejected under 35 U.S.C. 102(a)(1) and (a)(2) as being anticipated by Walker (WO 2022/015688).
Walker discloses a MgAl2O4 spinel body having a density of greater than 99.5% [0076] (i.e. less than 0.5% porosity) and a grain size of 0.5-20 microns [0024].
With respect to the claimed “a grain-preferred orientation (511)”, the XRD shows the body has an orientation (511) being one the largest peaks relative to the total number of peaks for the spinel body, thus “a grain-preferred orientation.”
Walker discloses that the body may be in the form of a ring, dome, window, nozzle, showerhead or injector [0049].
With respect to claims 2 and 8, note that the claimed limitation is a product by process claim limitation. This claim does not appear to distinguish over the reference as no difference in structure of the material is shown.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-2, 4-19 and 21-22 are rejected under 35 U.S.C. 103 as being unpatentable over Walker (WO 2022/015688) in view of Bram et al. (2019/0070818).
Walker discloses a MgAl2O4 spinel body having a density of greater than 99.5% [0076] (i.e. less than 0.5% porosity) and a grain size of 0.5-20 microns [0024].
With respect to the claimed “a grain-preferred orientation (511)”, the XRD shows the body has an orientation (511) being one the largest peaks relative to the total number of peaks for the spinel body, thus “a grain-preferred orientation.”
Walker discloses that the body may be in the form of a ring, dome, window, nozzle, showerhead or injector [0049].
Walker also discloses the method of manufacturing the ceramic article comprising the steps of: providing a green body by placing alumina and magnesia {00145] powder into a graphite die [00118]; heating the green body to a sintering temperature; compressing the green body at 5-60 MPa [00145]; applying an electric current to the green body thus forming a spinel structure [00145] wherein sintering takes place at 1700°C for less than 130 minutes [00123].
With respect to claims 2 and 8, note that the claimed limitation is a product by process claim limitation. This claim does not appear to distinguish over the reference as no difference in structure of the material is shown.
Walker does not specifically disclose sintering using an electrical pulse. [00118] discloses the SPS process preferably uses an unpulsed DC current. Bram et al. discloses that sintering ceramic materials may be carried out in a spark plasma sintering system using either direct current or pulsed current [0097]. It would have been prima facie obvious to one of ordinary skill, in the art as of the effective filing date, to modify, Walker with the recognized alternative pulsed process to produce the sintered product.
With respect to claim 17, it would have been obvious to one of ordinary skill in the art to determine the claimed current. Where 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).
With respect to claims 21 and 22, Walker discloses a MgAl2O4 spinel body having a density of greater than 99.5% [0076] (i.e. less than 0.5% porosity) and nearly dense or fully dense solid ceramic sintered body having correspondingly minimal porosity [0080]. Providing the spinel body with any porosity less than 0.5% such as between 0.06 and 0.1 vol%, would have been obvious to one of ordinary skill in the art to maximize the density of the spinel body.
Response to Arguments
Applicant's arguments filed August 27, 2025 have been fully considered but they are not persuasive.
Applicant argues that “preferred grain orientation” and “grain-preferred orientation” mean that the spinel structure has a preferential orientation along (511) plane.
However it is not clear from the specification nor the general knowledge that “preferred grain orientation” and “grain-preferred orientation” are in reference to the orientation that has the strongest (largest) peak in an XRD diagram or just in reference to one of the strongest peaks. The specification does not define these terms and in description of Fig. 9, refers to a structure with no preferred crystal orientation yet the Fig 9 XRD does have a strongest peak. A translation of reference of interest, CN 119980470, uses the terms “grain preferred orientation” or “preferred orientation” for Figs 1-3 in reference to peak (100) at 2theta 21.7, however in Figs 1-3, (100) is not always the strongest peak.
Applicant argues that independent Claim 7 further specifies that the spinel structure has not only a grain-preferred orientation (511), but also a particle size ranging between 10 and 40 pm and a porosity between 0.06 and 0.1 vol%.
Claim 7 has not been amended as stated to particle size ranging between 10 and 40 pm and a porosity between 0.06 and 0.1 vol%
Applicant argues that Walker does not specifically disclose sintering using an electrical pulse and further discloses in paragraph [00118] that SPS process preferably uses an unpulsed DC current. Starting from Walker, persons of ordinary skill in the art would not try to use any pulse current since Walker has explicitly disclosed that an unpulsed DC current is preferred. Bram discloses that the material to be sintered is heated up by a pulsed current or by a direct current in FAST/SPS methods (paragraph [0012], [0097]). However, the method disclosed in Bram is not used to manufacture a ceramic body including a spinel structure, let alone specifically the spinel (MgAl204) structure as disclosed by Walker. When studying how to produce a ceramic body including a spinel (MgAl204) structure, persons of ordinary skill in the art would not be motivated to refer to Bram's disclosure. Furthermore, Bram discloses either a pulsed current or by a direct current can be used in FAST/SPS methods, but it fails to teach which one is better or any advantage, which can be achieved by using a pulsed current. As Walker clearly teaches and suggests using an unpulsed DC current, persons of ordinary skill in the art would take Walker's advice to use an unpulsed DC current.
Applicant’s argument is not convincing because a preference is not a teaching away or limiting. While Walker teaches that the SPS process used “preferably uses an unpulsed, DC current,” Walker also incorporates by reference the procedure disclosed in US 2010/0156008 [00118] which does perform SPS using DC pulse currents. Thus Walker already incorporated use of pulsed DC current even without the teaching of Bram of pulsed current or direct current as alternatives.
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 MELVIN C MAYES whose telephone number is (571)272-1234. The examiner can normally be reached Mon-Fri 8:00am - 4:30pm.
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/MELVIN C. MAYES/Supervisory Patent Examiner, Art Unit 1759
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