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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 01/27/2026 has been entered.
Claim Objections
Claim 1 is objected to because of the following informalities:
In order to ensure proper antecedent basis, it is suggested to amend “the particles” to “the second population of platinum group metal particles” in claim 1, line 7.
Appropriate correction is required.
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 and 4-12 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 and 2 recite “a particle size distribution characterized by an average particle size”. However, it is not clear what is meant by "characterized by" or how the particle size distribution must be changed or modified in order to make it characterized by an average particle size. It is advised to delete “characterized by” in the claims.
Regarding dependent claims 4-12, these claims do not remedy the deficiencies of parent claim 1 noted above, and are rejected for the same rationale.
Claim 5 recites, “the plurality of platinum group metal particles has an average particle size of from about 3 to about 12”. However, claim 1 recites there are two population of particles with particles sizes ranging from about 0.5 nm to about 3 nm and from about 4 nm to about 8 nm. Therefore, it is unclear how the average particle size could be “about 12” as the upper limit when the particle size limit based on claim 1 is “about 8”. Clarification is requested.
Claim 11 recites, “Al2O3 doped with 1-10% SiO2, TiO2 doped with 1-20% SiO2, or ZrO2 doped with 1-30% SiO2”. However, it is unclear what these doping percentages are based on, i.e., weight percent, atomic percent, etc. For purposes of examination, the examiner interprets the percentages to be weight percentages. Clarification is requested.
Claim Rejections - 35 USC § 103
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.
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.
Claims 1-2, 4-10, and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Ogel et al. (“Impact of Preparation Method and Hydrothermal Aging on Particle Size Distribution of Pt/γ-Al2O3 and Its Performance in CO and NO Oxidation”, 2019) (Ogel), disclosed in the IDS filed 10/24/2025, and the Supplementary Information to “Impact of Preparation Method and Hydrothermal Aging on Particle Size Distribution of Pt/γ-Al2O3 and Its Performance in CO and NO Oxidation”.
Regarding claims 1, 7-10, and 12, Ogel teaches a series of Pt/Al2O3 catalysts for CO/NO oxidation (i.e., oxidation catalyst composition, the composition comprising a plurality of platinum group metal particles; claims 7 and 8, the platinum group metal is platinum; claims 9 and 10, comprising a refractory metal oxide support that is alumina) (Ogel, Abstract), wherein the catalysts include FSP-600 (formed by flame spray pyrolysis) which comprises a well-defined bimodal particle size distribution (Ogel, p. 5440, Col. 2, Paragraph 2), wherein the particle size distribution is displayed below.
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FSP-600 distribution in Figure S1
As seen above, the particle size distribution has two populations (i.e., claim 12, the first population of platinum group metal particles and the second population of platinum group metal particles are both fully dispersed on the same refractory metal oxide support), the first population having a range of particle sizes from about 0 to about 5 nm; and the second population having a range of particle sizes from about 5 nm to about 14 nm, which overlap with the ranges of the presently claimed particle sizes of the first and second populations.
Further, the majority of the particles in the second population have a particle size in the range of 5-10 nm which overlaps with the claimed average particle size of about 6 nm and at least 80% of the second population of platinum group metal particles having a particle size within 2 nm of the average particle size.
As set forth in MPEP 2144.05, in the case where the claimed range “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists, 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).
Regarding claim 2, Ogel teaches the oxidation catalyst composition of claim 1, wherein based on Figure S1(b), the first population has an average particle size of about 1 nm and a majority of the particle sizes in the first population are between 0 and 3 nm, which overlaps with the range of the presently claimed.
As set forth in MPEP 2144.05, in the case where the claimed range “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists, 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).
Regarding claim 4, Ogel teaches the oxidation catalyst composition of claim 1, wherein the first population comprises roughly 1200 counts and the second population comprises roughly 450 counts (Ogel, Figure S1(b)), therefore the ratio between the first and second group is roughly 8:3 which equals 10:3.75, which falls within the claimed range.
Regarding claim 5, Ogel teaches the oxidation catalyst composition of claim 1, wherein the average particle size of all of the platinum particles is 3.8 nm (Ogel, Figure S1(b)), which falls within the claimed range.
Regarding claim 6, Ogel teaches the oxidation catalyst composition of claim 1, wherein it is not explicitly stated that at least 90% of the platinum group metal in FSP-600 is in fully reduced form, however Ogel teaches that the oxidation mechanism of NO to NO2 involves reduced Pt nanoparticles (Ogel, p. 5444, Col. 1, Paragraph 2). Therefore, one of ordinary skill in the art would know that in order for the catalysts to be useful in the oxidation of NO to NO2, the Pt would need to be in reduced form.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Ogel, as applied to claim 10 above, and further in view of Uchisawa et al. (“Effects of the Extent of Silica Doping and the Mesopore Size of an Alumina Support on Activity as a Diesel Oxidation Catalyst”, 2014) (Uchisawa).
Regarding claim 11, Ogel teaches the oxidation catalyst composition of claim 10, but does not explicitly teach the support is Al2O3 doped with 1-10% SiO2, TiO2 doped with 1-20% SiO2, or ZrO2 doped with 1-30% SiO2.
With respect to the difference, Uchisawa teaches a platinum oxidation catalyst with an SiO2 doped alumina support, wherein the highest catalytic activity was obtained using 4 wt% SiO2 loading (Uchisawa, Abstract), which falls within the claimed range.
As Uchisawa expressly teaches, the thermal stability of Al2O3 is increased by SiO2 doping (Uchisawa, p. 7992, Col. 2, Paragraph 1), and wherein the positive effect induced by adding the silica is likely due to the optimization of the basicity of the support (Uchisawa, p. 7998, Paragraph 1).
Uchisawa is analogous art as it is drawn to a platinum oxidation catalyst supported on alumina (Uchisawa, Abstract).
In light of the motivation of doping the alumina support with 4 wt% silica as disclosed by Uchisawa, it therefore would have been obvious to one of ordinary skill in the art to modify the alumina support of Ogel by doping the alumina support with 4 wt% silica in order to increase the thermal stability by optimizing the basicity of the support, and thereby arrive at the claimed invention.
Response to Arguments
After further consideration, a new claim objection and new set of 35 U.S.C. 112(b) rejections over claims 1-2 and 4-12 are set forth above.
In response to the amendment regarding a second population of platinum group metal particles having a range of particle sizes of from about 4 nm to about 8 nm and based on applicant’s remarks filed on pages 5-6 regarding the 35 U.S.C. 103 rejection over Leistner in view of Miyamoto, and over Wei in view of Miyamoto it is agreed that Leistner in view of Miyamoto and Wei in view of Miyamoto would not meet the present claims. However, the amendment necessitates a new set of rejection as set forth above using Ogel.
Conclusion
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/C.M.C./Examiner, Art Unit 1732
/CORIS FUNG/Supervisory Patent Examiner, Art Unit 1732
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