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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 01/20/2026 has been entered.
This action is responsive to Applicant’s request for continued examination and amendment/remarks filed 01/20/2026.
Claims 8 and 20 are currently pending.
The IDS filed 12/22/2025 have been considered. Initialed copies accompany this action.
Claim Rejections - 35 USC § 102 & 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.
Claim 20 is rejected under 35 U.S.C. 102(a)(1,2) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Sobajima et al. (US 3,947,373 A).
Sobajima et al. teach a powder comprising a core of magnesium oxide particles surrounded by a sheath of a double oxide of the magnesium oxide and boron oxide and optionally another metal oxide (abstract). The optional other metal oxide is at least one of titanium oxide, iron oxide, and chromium oxide (abstract; see also col. 5 lines 6-15 and col. 6 line 64 to col. 7 line 10). This corresponds to a magnesia (MgO) comprising a MgO granule (the magnesium oxide core) and a surface oxide layer formed on the surface of the MgO granule (the sheath containing oxides surrounds the magnesium oxide core) wherein the surface oxide layer comprises the MgO and a donor (the sheath contains the magnesium oxide, i.e., the MgO, and at least one other oxide, i.e., a donor). Since the core comprises magnesium oxide particles and the sheath comprises a mixture of oxides (Id.), a composition of the surface oxide layer (sheath) is clearly different from a composition inside the MgO granule (the magnesium oxide core) and a content of the donor inside the surface oxide layer is clearly higher than that inside the granule (the core is magnesium oxide and the sheath contains the additional oxides that read on the donor).
Sobajima et al. specifically teach several working examples which have thicknesses of the surface oxide layer (the sheath) within the claimed range of greater than zero microns and less than or equal to three microns. See Examples 25, 30, 31, 32, and 33 in Table 2 of Sobajima et al. which have sheath thicknesses, in microns, of 2.9, 2.9, 2.5, 0.4, and 0.4, respectively. These examples anticipate the claimed surface oxide layer thickness range (and the relative composition/content limitation(s) for the reasons described above, Id.). The final remaining limitation regarding the density of the surface oxide layer being higher than the density inside the MgO granule is presumed inherent from the teachings of Sobajima et al. Sobajima et al. teach the sheath covers and envelopes the entire surface of the core and must not be porous or cracked (col. 5 lines 16-17 and col. 7 lines 50-56) which teaches the sheath/surface oxide layer is indeed relatively dense. In any event, Sobajima et al. specifically teach a magnesia powder with the same composition as that claimed (a MgO granule with a sheath/surface oxide layer formed on its surface comprising MgO and a donor, MgO and B2O3 in the specifically-cited examples), and it is well established that products of identical chemical composition can not have mutually exclusive properties.
In the event the above-cited teachings of the reference are somehow insufficient to meet the claimed limitations (e.g., the surface oxide layer thickness and/or relative density) under the meaning of anticipation, the claimed limitations are alternatively prima facie obvious over the teachings the Sobajima et al.:
Regarding the thickness of the oxide sheath layer, i.e., the thickness of the surface oxide layer, under an obviousness rationale, Sobajima et al. teach the preferred thickness of the sheath is not more than 50%, usually 2 to 30%, of the average particle size of the powder (col. 5 lines 24-27). Regarding the average particle size of the powder, Sobajima et al. teaches the particle size of the starting MgO is selected according to the desired size of the final obtained calcined product (the MgO core coated with the oxide sheath) and is usually MgO having an average particle size of about 30 to about 8000 Tyler’s mesh (col. 8 lines 16-21). While it is noted this teaching is to the particle size of the starting MgO rather than the particle size of the final product (the coated MgO), Sobajima et al. nevertheless further teach the magnesium oxide maintains its particle size after calcination (col. 7 lines 57-61). The working examples also confirm this (every successful working example among Tables 1 & 2 have the same initial magnesia average particle size and finally obtained average particle size after calcination – see, for example, Ex. 1 which starts with a 400 mesh magnesia and ends with a 400 mesh final calcined product, Ex. 12 which starts with a 35 mesh magnesia and ends with a 35 mesh final calcined product, Ex. 25 which starts with a 400 mesh magnesia and ends with a 400 mesh final calcined product, Ex. 32 which starts with a 4000 mesh magnesia and ends with a 4000 mesh final calcined product). Accordingly, the beginning magnesia particle size equals the particle size of the final product, meaning the finally obtained oxide sheath-coated magnesia powder of Sobajima et al. have a preferred average particle size of about 30 to about 8000 Tyler’s mesh. It is well-known in the art that particle sizes in microns (µm) can be calculated from Tyler’s mesh sizes by the formula 14900/mesh, that is, dividing the number 14,900 by the Tyler’s mesh size. Accordingly, Sobajima et al.’s finally obtained oxide sheath-coated magnesia powder of Sobajima et al. have a preferred average particle size of about 2 microns (14,900/8,000) to about 497 microns (14,900/30). Since Sobajima et al. teach the sheath thickness is usually 2 to 30% of the average particle size of the powder (Id.), it is an express and/or preferred teaching in the reference that the sheath/surface oxide layer has a thickness of at least about 0.04 microns (2% of about 2 microns), which certainly overlaps the claimed surface oxide layer thickness range.
Regarding the relative density limitation that the surface oxide layer has a higher density than the MgO core/granule under an obviousness rationale, this relative claim limitation would nevertheless flow naturally from the teachings of the reference as Sobajima et al. teaches/motivates substantially the same exact structural configuration as disclosed by Applicant possessing this feature. Applicant has disclosed addition/coating of metal oxide “donors” such as boron oxide, titanium oxide, iron oxide, etc. on a magnesia/MgO particle forms a dense surface oxide layer and has a higher relative density over that of magnesia/MgO alone (p.10, 11, 12, & 14, spec.; see also Table 1). Again, note that Sobajima et al. teach the sheath covers and envelopes the entire surface of the core and must not be porous or cracked (Id. at col. 5 lines 16-17 and col. 7 lines 50-56) and further teach the power has superior moisture resistance (col. 1 lines 9-11), which further evidences the sheath/surface oxide layer is indeed dense or else the coating would not be able to block the MgO powder from absorbing moisture. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985) ("The fact that appellant has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious.").
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Kawada (JP 56-061740 A). The Office previously supplied an English language machine translation of Kawada attached to the copy of the reference, and citations to Kawada are with respect to the translation unless specified otherwise.
Kawada teaches MgO particles coated with a surface layer of TiO2 (abstract). See also p.2 of the English language machine translation attached to the supplied copy of the reference. See also Fig. 2. Note that Fig. 2 depicts the particles as spherical. The TiO2 coating serves to improve (lower) the MgO from absorbing moisture (p.2).
Kawada teaches the thickness of the TiO2 coating “is preferably several tens to several hundreds of angstroms” (Id. on p.2 of the translation). A person of ordinary skill in the art would understand and reasonably interpret the term “several” as is used in the reference as meaning a small number greater than two such as three, four, or five such that several tens of angstroms would include and encompass thirty to fifty angstroms as a lower boundary of the thickness and several hundreds of angstroms would include and encompass three hundred to five hundred angstroms as an upper boundary of the thickness. Also, there are ten thousand angstroms per micron. Accordingly, a coating thickness of several tens to several hundreds of angstroms includes and encompasses a thickness of approximately 30 to 500 angstroms which is equivalent to a thickness of approximately 0.003 to 0.05 microns.
Meanwhile, Kawada also teaches and describes the final coated particles as “microcapsules” (Id. on p.2 of the translation), meaning the MgO are microparticles having a diameter/size on the order of microns, i.e., somewhere between, including, and/or encompassing 1 to 1,000 microns. In sum and in other words, because the MgO are microparticles having a diameter/size somewhere between, including, and/or encompassing 1 to 1,000 microns (Id.) and the coating thereon includes and/or encompasses a thickness of approximately 0.003 to 0.05 microns, the coated MgO particles may clearly contain several orders of magnitude more MgO than TiO2/coating.
Kawada fails to explicitly teach the MgO particles/microcapsules are specifically represented by the formula MgO + x wt.% TiO2 + y wt.% of additional metal oxide donor(s) is ≤ 100 wt.% where x and y are each greater than 0 wt.% and less than or equal to 2 wt.% and MgO is equal to and greater than 98 wt.% and less than 100 wt.%.
However, Kawada further teaches Al2O3 and Ga2O3 can also be used as the moisture-resistant material, i.e., coating, for the MgO capsule (see sentence bridging p.2 to 3 of the translation). In other words, Kawada et al. teach and recognize all of TiO2, Al2O3, and Ga2O3 are equivalent moisture-resistant materials for coating MgO.
Thus, at the time of the effective filing date it would have been obvious to further combine one of Al2O3 or Ga2O3 with TiO2 and in surface oxide coating on the MgO particle in Kawada in order to obtain a moisture resistant coating of TiO2+Al2O3, TiO2+Ga2O3, and/or TiO2+Al2O3+Ga2O3 on the MgO surface with a reasonable expectation of success.
It is prima facie obvious to combine two compositions each of which is taught by the prior art to be useful for the same purpose, in order to form a third composition to be used for the very same purpose.... [T]he idea of combining them flows logically from their having been individually taught in the prior art." In re Kerkhoven, 626 F.2d 846, 850, 205 USPQ 1069, 1072 (CCPA 1980) (citations omitted) (Claims to a process of preparing a spray-dried detergent by mixing together two conventional spray-dried detergents were held to be prima facie obvious.). See also In re Crockett, 279 F.2d 274, 126 USPQ 186 (CCPA 1960) (Claims directed to a method and material for treating cast iron using a mixture comprising calcium carbide and magnesium oxide were held unpatentable over prior art disclosures that the aforementioned components individually promote the formation of a nodular structure in cast iron.); Ex parte Quadranti, 25 USPQ2d 1071 (Bd. Pat. App. & Inter. 1992) (mixture of two known herbicides held prima facie obvious); and In re Couvaras, 70 F.4th 1374, 1378-79, 2023 USPQ2d 697 (Fed. Cir. 2023) (That the two claimed types of active agents, GABA-a agonists and ARBs, were known to be useful for the same purpose—alleviating hypertension—alone can serve as a motivation to combine).
The above modification of the reference meets, arrives within, and/or arrives at concentrations overlapping the claimed formula and concentrations thereof where MgO + x wt.% TiO2 + y wt.% of additional metal oxide donor(s) (i.e., Al2O3 and/or Ga2O3) is ≤ 100 wt.% where x and y are each greater than 0 wt.% and less than or equal to 2 wt.% and MgO is equal to and greater than 98 wt.% and less than 100 wt.% because the obtained coated MgO particles/microcapsules contain primarily/mostly MgO the MgO is present as microparticles having a diameter/size on the order of microns (1-1,000 microns, Id.) and the thickness of the coating is on the order of tens to hundreds of angstroms (0.003-0.05 microns, Id.) where there may several orders of magnitude more MgO than oxides (e.g., TiO2, Al2O3, and/or Ga2O3) in the coating. Since the diameters and thickness of the portions of microcapsule can be quantitatively approximated via the reference’s terminology and descriptions of the microcapsule and its coating thickness, relative volumes of the core portion of the microcapsule and coating portion/layer of the microcapsule can be easily calculated. Volume of a spherical particle, i.e. core, can be easily calculated/approximated by the formula 4/3×π×r3 where r is the radius of the particle/core; note that a radius is half of a diameter, e.g., r = d/2. Volume of a coating on a spherical particle can be easily calculated/approximated by the formula 4/3×π×((r1+r2)3-r13) where r1 is the radius of the core/particle itself (and half of its diameter, Id.) and r2 is the radius/thickness of the of the coating on the particle. Because the term “several” as is used in the reference means, e.g., three, four, or five, a variety of relative volumes of the of the core and coating portions of the reference’s can be calculated and are encompassed by the teachings of the reference. The following Tables are results of relative volumes of the core and coating portions of the coated MgO particles encompassed by the cited teachings of the reference for when “several” equals three, four, and five:
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146
437
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146
437
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146
437
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For clarity, the meaning of “when ‘several’ equals three” means the thickness of the coating under the interpretation the term “several” in the teaching the coating “is preferably several tens to several hundreds of angstroms” is/includes/encompasses three tens, i.e., thirty, to three hundreds, i.e., three hundred, angstroms. Similarly, the meaning of “when ‘several’ equals four” means the thickness of the coating under the interpretation the term “several” in the teaching the coating “is preferably several tens to several hundreds of angstroms” is/includes/encompasses four tens, i.e., forty, to four hundreds, i.e., four hundred, angstroms, and the meaning of “when ‘several’ equals five” means the thickness of the coating under the interpretation the term “several” in the teaching the coating “is preferably several tens to several hundreds of angstroms” is/includes/encompasses five tens, i.e., fifty, to five hundreds, i.e., five hundred, angstroms.
Accordingly, a person of ordinary skill in the art would readily understand the above relative volumes (vol.%) encompassed by the reference can be converted to relative weights (wt.%) and/or determined by routine means, and, after doing so, would clearly amount to each of TiO2, Al2O3, and/or Ga2O3 being within or overlapping the recited individual amounts of greater than 0 wt.% and less than or equal to 2 wt.% as well as MgO is being within or overlapping the recited amount of equal to and greater than 98 wt.% and less than 100 wt.%, as recited.
Additionally, the modification of the reference amounts a MgO granule (the disclosed MgO particles/powder) having a surface oxide layer formed on a surface of the MgO granule (the coating of TiO2+Al2O3, TiO2+Ga2O3, and/or TiO2+Al2O3+Ga2O3) where a composition of the surface oxide layer is different from a composition inside the MgO granule (a coating of TiO2+Al2O3, TiO2+Ga2O3, or TiO2+Al2O3+Ga2O3 clearly has a composition different from a composition inside the MgO granule, i.e., TiO2+Al2O3, TiO2+Ga2O3, or TiO2+Al2O3+Ga2O3 is different than MgO) and a content of a donor inside the surface oxide layer is higher than that inside the granule (a coating of TiO2+Al2O3, TiO2+Ga2O3, or TiO2+Al2O3+Ga2O3 clearly has a content of more TiO2, Al2O3, and/or Ga2O3 inside said coating relative to TiO2, Al2O3, and/or Ga2O3 present inside a MgO granule/core) as claimed.
While Kawada does not explicitly disclose that the density of the TiO2 coating on their MgO particles has a density higher than the non-coated MgO particles or MgO core as claimed, this relative claim limitation is presumed inherent from the teachings of the reference and/or would flow naturally from the teachings of the reference as Kawada teaches/motivates substantially the same exact structural configuration as disclosed by Applicant possessing this feature. Applicant has disclosed addition/coating of TiO2 and additional metal oxide “donors” on a magnesia/MgO particle forms a dense surface oxide layer and has a higher relative density over that of magnesia/MgO alone (p.10, 11, 12, & 14, spec.; see also Table 1). Note that Kawada further teach the coating improves (lowers) the MgO from absorbing moisture (p.2), further evidencing the coating is indeed dense or else the coating would not be able to block the MgO powder from absorbing moisture. See MPEP 2112 and Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985) ("The fact that appellant has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious.").
Response to Arguments
Applicant's arguments filed 01/20/2026 have been fully considered but they are not persuasive.
Regarding the 102/103 rejection over Sobajima et al. (US 3,947,373 A) Applicant argues Sobajima et al. fail to teach or suggest the claimed relative density of the surface oxide layer versus the MgO granule limitation and that the limitation is not necessarily present in the reference. Applicant’s position is that the reference does not measure or compare density nor teach/indicate the sheath/oxide coating is more compact than the interior of the granule.
In response, this argument is not persuasive because, under an anticipation rationale, Sobajima et al. teach the sheath covers and envelopes the entire surface of the core and must not be porous or cracked (col. 5 lines 16-17 and col. 7 lines 50-56) which teaches the sheath/surface oxide layer is indeed relatively dense. Sobajima et al. specifically teach a magnesia powder with the same composition as that claimed (a MgO granule with a sheath/surface oxide layer formed on its surface comprising MgO and a donor, MgO and B2O3 in the specifically-cited examples), and it is well established that products of identical chemical composition can not have mutually exclusive properties.
Furthermore, under an obviousness rationale, as cited in the rejection of the record and in addition to the teachings that the coating is nonporous, Sobajima et al. teach the oxide coating may optionally contain another metal oxide such as titanium oxide, iron oxide, and chromium oxide. Transition metal oxides are more dense than magnesium oxide. Thus, a nonporous oxide containing a transition metal oxide in addition to magnesium oxide (Sobajima et al.'s coating of the powder) would be expected by a person of ordinary skill in the art to be more dense than the same magnesium oxide along (i.e., Sobajima et al.'s magnesium oxide core of the powder). This is one reason why the claimed limitation would flow naturally from the cited teachings of the reference. Additionally, this relative claim limitation would nevertheless flow naturally from the teachings of the reference as Sobajima et al. teaches/motivates substantially the same exact structural configuration as disclosed by Applicant possessing this feature. Applicant has disclosed addition/coating of metal oxide “donors” such as boron oxide, titanium oxide, iron oxide, etc. on a magnesia/MgO particle forms a dense surface oxide layer and has a higher relative density over that of magnesia/MgO alone (p.10, 11, 12, & 14, spec.; see also Table 1). Again, note that Sobajima et al. teach the sheath covers and envelopes the entire surface of the core and must not be porous or cracked (Id. at col. 5 lines 16-17 and col. 7 lines 50-56) and further teach the power has superior moisture resistance (col. 1 lines 9-11), which further evidences the sheath/surface oxide layer is indeed dense or else the coating would not be able to block the MgO powder from absorbing moisture. Provision of a relatively dense oxide coating is motivated by these teachings in order for the oxide coating to block the MgO powder from absorbing moisture.
Regarding Applicant’s concern of the prior art failing to specifically quantify the densities of the oxide coating and the underlying MgO core/powder, the discovery of a previously unappreciated property of a prior art composition (i.e., discovery of a relative density of the oxide coating having a higher density than the powder core) does not render the old composition patentably new to the discoverer. Inherent features of a prior art reference and/or features that would flow naturally from a prior art reference need not be recognized at the relevant time. See, for example, Atlas Powder Co. v. IRECO Inc., 190 F.3d 1342, 1347, 51 USPQ2d 1943, 1947 (Fed. Cir. 1999).
Applicant further argues Sobajima et al. fail to teach or suggest the claimed relative content of donor inside the surface oxide layer versus the MgO granule limitation and that the limitation is not necessarily present in the reference. Applicant’s position is that, while the reference discloses forming a sheath containing additional oxides relative to the MgO core, Sobajima et al. merely indicates the donor oxides are present at the surface not that the donor concentration is higher than within the interior of the granule in the relational manner required by the claim. Applicant elaborates the claim requires a specific compositional gradient where the donor is enriched at the surface relative to the granule interior and the reference has no disclosure of donor migration, redistribution, or surface enrichment.
In response, this argument is not persuasive because the cited teachings of the reference plainly meet the claimed limitation that “a content of the donor inside the surface oxide layer is higher than that inside the granule”. Sobajima et al. teach a powder comprising a core of magnesium oxide particles surrounded by a sheath of a double oxide of the magnesium oxide and boron oxide and optionally another metal oxide. This corresponds to a MgO granule (the magnesium oxide core) and a surface oxide layer formed on the surface of the MgO granule (the sheath containing oxides surrounds the magnesium oxide core) wherein the surface oxide layer comprises the MgO and a donor (the sheath contains the magnesium oxide, i.e., the MgO, and at least one other oxide, i.e., a donor). Since the core comprises magnesium oxide particles and the sheath comprises a mixture of oxides (Id.), a content of the donor inside the surface oxide layer is clearly higher than that inside the granule (the core is magnesium oxide and the sheath contains the additional oxides that read on the donor). Said differently, Sobajima et al.’s core (that is coated by the oxide sheath/coating) is magnesium oxide, meaning that the core is only magnesium oxide and the oxide coating contains magnesium oxide with additional components (the other oxides) – this precisely describes a content of the donor (other non-MgO oxides) inside the surface of the surface oxide layer (the oxide coating) is higher than that inside the granule (the magnesium oxide core portion).
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., a concentration gradient, donor migration, donor redistribution, etc.) is not recited in the rejected claim. Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Applicant further submitted a 132 Declaration on 01/23/2026 to proffer the nonobviousness of the claimed invention over the teachings of Sobajima et al.
Page 1 of the declaration provides a summary of the declarant’s background. Pages 1 & 2 of the declaration preface experimental data (Supplementary Data 8 and 9), and page 3 & 4 present the experimental data, which appear to be potential eutectics formed by Ti4+ and Nb5+ that do not occur with Li1+ or Zn2+ and depict the potential for Mg to volatize under certain conditions. Page 5 of the declaration presents and explains Supplementary Data 10, which is various results of a 1400°C sintering with no additive or one of Li+, Zn2+, Ti4+, Nb5+, or Ti4+ & Nb5+. Page 6 of the declaration presents and explains Supplementary Data 11, which is a potential liquid phase formation in MgO when Ti4+ and Nb5+ are donors during sintering. Page 7 of the declaration is a conclusion section with the declarant’s signature and date.
Applicant substantially repeats the content of the declaration on pages 8-13 of the response filed 01/20/2026. Applicant then further argues Sobajima et al. has a completely different mechanism than the present invention and cannot derive the claimed features because Sobajima et al. requires what is alleged as an excessive amount of oxide to cover the entire surface of the MgO core particles. Applicant also argues Sobajima et al.’s moisture resistance meaning their sheath/oxide layer is dense is premised on hindsight.
After careful and full consideration of its content, the declaration under 37 CFR 1.132 filed 01/23/2026 and corresponding remarks filed 01/20/2026 are insufficient to overcome the rejection of record over Sobajima et al.
First, evidence of secondary considerations (i.e., the Supplementary Data to narrow, specific embodiments of the claimed invention present in the 132 declaration) irrelevant to 35 U.S.C. 102 rejections and thus cannot overcome a rejection so based. See, for example, In re Wiggins, 488 F.2d 538, 543, 179 USPQ 421, 425 (CCPA 1973).
The data in the 132 declaration does not compare the claimed invention with the closest prior art of record. The declaration’s comparison of coated MgO granules utilizing one oxide of lithium, zinc, titanium, niobium, both titanium and niobium, or no donor does not serve as a direct or fair comparison the coated MgO powder/granules utilizing boron oxide and optionally one of titanium oxide, iron oxide, and chromium oxide taught by Sobajima et al. An affidavit or declaration under 37 CFR 1.132 must compare the claimed subject matter with the closest prior art to be effective to rebut a prima facie case of obviousness. In re Burckel, 592 F.2d 1175, 201 USPQ 67 (CCPA 1979). Also note the rejected claim is much more broad than the narrow embodiments shown in the comparative data, and the claims are not commensurate in scope with the declaration’s showing.
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’s characterization that Sobajima et al.’s amount of oxide to cover the MgO core particles is excessive is an opinion without evidence and not persuasive for that reason. Arguments presented by the applicant cannot take the place of evidence in the record. See In re Schulze, 346 F.2d 600, 602, 145 USPQ 716, 718 (CCPA 1965) and In re De Blauwe, 736 F.2d 699, 705, 222 USPQ 191, 196 (Fed. Cir. 1984).
Regarding the 103 rejection over Kawada (JP 56-061740 A) Applicant argues Kawada fails to teach or suggest the claimed relative density of the surface oxide layer versus the MgO granule limitation and that the limitation is not necessarily present in the reference. Applicant’s position is that the reference does not measure or compare density nor teach/indicate the oxide coating layer is more compact than the interior of the granule.
In response, this argument is not persuasive because, Kawada teach the oxide coating is produced by chemical vapor deposition (p.2), which typically forms a dense coating layer. Kawada further teach the coating as a “capsule film” and forms a microcapsule (p.2) which implies the coating layer as dense because forming a capsule film or encapsulation of the underlying substance (MgO) effectively seals/encapsulates the core inside the coating or else a “capsule film” would not be formed. As cited in the rejection of record, Kawada teach the oxide coating is made of TiO2, Al2O3, and/or Ga2O3. These metal oxides are more dense than magnesium oxide. Thus, a coating of these oxide(s) made in the manner as taught and suggested by Kawada to encapsulate an underlying MgO particle would be expected by a person of ordinary skill in the art to be more dense than MgO particle. This is one reason why the claimed limitation would flow naturally from the cited teachings of the reference. Additionally, this relative claim limitation would nevertheless flow naturally from the teachings of the reference as Kawada teach/motivate substantially the same exact structural configuration as disclosed by Applicant possessing this feature. Applicant has disclosed addition/coating of TiO2 and additional metal oxide “donors” on a magnesia/MgO particle forms a dense surface oxide layer and has a higher relative density over that of magnesia/MgO alone (p.10, 11, 12, & 14, spec.; see also Table 1). Note that Kawada further teach the coating improves (lowers) the MgO from absorbing moisture (p.2), further evidencing the coating is indeed dense or else the coating would not be able to block the MgO powder from absorbing moisture. See MPEP 2112 and Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985) ("The fact that appellant has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious.").
Regarding Applicant’s concern of the prior art failing to specifically quantify the densities of the oxide coating and the underlying MgO core/powder, the discovery of a previously unappreciated property of a prior art composition (i.e., discovery of a relative density of the oxide coating having a higher density than the powder core) does not render the old composition patentably new to the discoverer. Features that would flow naturally from a prior art reference need not be recognized at the relevant time. See, for example, Atlas Powder Co. v. IRECO Inc., 190 F.3d 1342, 1347, 51 USPQ2d 1943, 1947 (Fed. Cir. 1999).
Applicant further argues Kawada fails to teach or suggest the claimed relative content of donor inside the surface oxide layer versus the MgO granule limitation and that the limitation is not necessarily present in the reference. Applicant’s position is that, while the reference discloses depositing an oxide (e.g., TiO2) onto a MgO surface to form a coating, Kawada does not teach or suggest the donor concentration in the surface layer much exceed that inside the granule in the relational manner claimed. Applicant further argues Kawada does not describe donor migration, redistribution, or any mechanism that would produce a compositional gradient.
In response, this argument is not persuasive because the cited teachings of the reference plainly meet the claimed limitation that “a content of the donor inside the surface oxide layer is higher than that inside the granule”. As set forth in the rejection of record, the obvious modifications motivated by the cited teachings and suggestions of the reference amount to a MgO granule (the disclosed MgO particles/powder) having a surface oxide layer formed on a surface of the MgO granule (the coating of TiO2+Al2O3, TiO2+Ga2O3, and/or TiO2+Al2O3+Ga2O3) where a content of a donor inside the surface oxide layer is higher than that inside the granule (a coating of TiO2+Al2O3, TiO2+Ga2O3, or TiO2+Al2O3+Ga2O3 clearly has a content of more TiO2, Al2O3, and/or Ga2O3 inside said coating relative to TiO2, Al2O3, and/or Ga2O3 present inside a MgO granule/core) as claimed. Since the core comprises magnesium oxide particles and the sheath comprises distinct oxides (Id.), a content of the donor inside the surface oxide layer is clearly higher than that inside the granule (the core is magnesium oxide and the sheath contains the distinct oxides that read on the donor). Said differently, Kawada’s core (that is coated by the oxide sheath/coating) is magnesium oxide, meaning that the core is only magnesium oxide and the oxide coating contains other non-MgO oxide components (the other, distinct oxides) – this precisely describes a content of the donor (other non-MgO oxides) inside the surface of the surface oxide layer (the oxide coating) is higher than that inside the granule (the magnesium oxide core portion).
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., a concentration gradient, donor migration, donor redistribution, etc.) is not recited in the rejected claim. Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Applicant further submitted a 132 Declaration on 01/23/2026 to proffer the nonobviousness of the claimed invention over the teachings of Kawada. A summary of the declaration is set forth above in response to arguments over Sobajima et al. and is not repeated here for purposes of brevity.
Applicant substantially repeats the content of the declaration on pages 17-22 of the response filed 01/20/2026. Applicant then further argues Kawada has a completely different mechanism than the present invention because Kawada uses a separate thin film layer composed of TiO2, Al2O3, or Ga2O3 that is completely devoid of MgO and is completely different than the claimed invention requiring a surface oxide layer including MgO and a donor.
After careful and full consideration of its content, the declaration under 37 CFR 1.132 filed 01/23/2026 and corresponding remarks filed 01/20/2026 are insufficient to overcome the rejection of record over Kawada.
As similarly explained above regarding Sobajima et al., the data in the 132 declaration does not compare the claimed invention with the closest prior art of record. The declaration’s comparison of coated MgO granules utilizing one oxide of lithium, zinc, titanium, niobium, both titanium and niobium, or no donor does not serve as a direct or fair comparison the coated MgO powder/granules utilizing TiO2, Al2O3, Ga2O3, and mixtures thereof taught, suggested, and/or motivated by Kawada. An affidavit or declaration under 37 CFR 1.132 must compare the claimed subject matter with the closest prior art to be effective to rebut a prima facie case of obviousness. In re Burckel, 592 F.2d 1175, 201 USPQ 67 (CCPA 1979). Also note the rejected claim is much more broad than the narrow embodiments shown in the comparative data, and the claims are not commensurate in scope with the declaration’s showing.
In response to applicant's argument that Kawada fails to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., a surface oxide layer including MgO and a donor, etc.) are not recited in the rejected claim. Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Accordingly, the rejections are maintained for the reasons of record.
Prior Art Cited But Not Applied
The following prior art is made of record and not relied upon but is considered pertinent to Applicant's disclosure and/or as evidence supporting the rejection of record:
TW 201020085 A is a cited reference of record that teaches and serves as evidence it is well-known in the art that particle sizes in microns (µm) can be calculated from Tyler mesh sizes by the formula 14900/mesh, that is, dividing the number 14,900 by the Tyler mesh size. See, page 8 of the original document, which contains the excerpt, in Taiwanese:
PNG
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162
508
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which translates to:
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131
501
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Greyscale
The remaining references listed on Forms 892 and 1449 have been reviewed by the examiner and are considered to be cumulative to or less material than the prior art references relied upon or discussed above.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MATTHEW R DIAZ whose telephone number is 571-270-0324. The examiner can normally be reached Monday-Friday 9:00a-5:00p EST.
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/MATTHEW R DIAZ/Primary Examiner, Art Unit 1761
/M.R.D./
June 4, 2026
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