Detailed Office Action
Notice of Pre-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
Response to Amendments
The amendment filed on 12/29/2025 has been entered. Claims 1 – 5, 8 – 15, and 17 – 20 are pending. Claims 9 – 10 and 17 – 20 remain withdrawn. Claims 1 – 5, 8, and 11 – 15 are under examination.
Claim Interpretation
For clarity of the record, the examiner notes that the constituents of “M” (comprising, Cu, Al, and Ga) is interpreted as also referring to the “M” of the HR-M alloy. To specify, the “M” of the HR-M alloy is interpreted as comprising Cu, Al, and Ga.
Claim Warning
Applicant is advised that should claim 8 be found allowable, claim 15 will be objected to under 37 CFR 1.75 as being a substantial duplicate thereof. When two claims in an application are duplicates or else are so close in content that they both cover the same thing, despite a slight difference in wording, it is proper after allowing one claim to object to the other as being a substantial duplicate of the allowed claim. See MPEP § 608.01(m).
Claim Rejections – U.S.C. §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.
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.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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 – 5, 8, and 11 – 15 are rejected under 35 U.S.C. 103 as being unpatentable over Hidaka (US2017/0103835, cited in the OA on 01/22/25) in view of Miyata (US2011/0210810, cited in the OA 08/09/24) and in further view of Sun (WO2012/013086, using machine translation, cited in the OA on 04/30/25)
Regarding claim 1, Hidaka teaches an RTB magnet produced by sintering and diffusing an alloy into the magnetic work [Abstract, 0044], wherein the RTB magnet has a main phase [0067], meeting the claimed limitation of a sintered green body with main phase.
Hidaka teaches an exemplary alloy composition which meets the claimed range [Table 2, Example 40].
Element
Nd + Tb (“R”)
B
Al
Ga
Cu
Co
Mn
Zr
Fe
Mass%
30.64
0.9
0.2
0.2
0.2
2.0
0.04
0.15
65.67
Hidaka teaches that the sintered magnetic work can be subjected to diffusion treatment using a compound or alloy containing Tb on the surface of the sintered magnet and subjecting it to the diffusion treatment [0100, 0102]. Wherein, from a diffusion surface/plane, given that “any two points spaced from the diffusion plane by a distance of no more than 500 µm” can include two points essentially next to each (i.e. a distance of ~0 µm), two points this close would possess a ratio of HR content that was approximately identical (i.e. ~1.0), meeting the claimed range/ratio. Additionally, Hidaka teaches that the concentration ratio of Tb at the surface to Tb at the core is 0.4 – 1.0 [0065].
The examiner notes that the claims are directed to a product and a product is not limited by the manipulation of the recited steps, only the structure implied (MPEP 2113 I), wherein Hidaka discloses using a sintered magnet in the diffusion treatment. However, for purposes of compact prosecution the examiner notes that Hidaka teaches the sintered magnet is produced by strip casting the magnet alloy composition, introduction hydrogen into the alloy and pulverizing, then molding the alloy powder in a magnetic field [0120, 0121, 0125], meeting the claimed steps.
Hidaka does not explicitly teach that the heavy rare earth used in diffusion treatment is applied to at least one non-orientation plane (a plane that is not perpendicular to the magnetization direction). Hidaka discloses that Tb (interpreted as the heavy rare earth) can be used in the form of an alloy [0100], but does not explicitly teach the composition of said alloy.
Miyata teaches a R-Fe-B sintered magnet subjected to diffusion treatment [Title, 0029]. Miyata teaches that the diffusion treatment is with a Dy or Tb diffusion source which is applied to non-perpendicular surfaces of the magnet for diffusion, meeting the claimed limitation of having several surfaces and applying HR such that diffusion takes place within a perpendicular direction to the magnetization [Claim 1, Fig 1A]. Miyata explicitly states “that by providing a sintered Nd base magnet block (sintered rare earth magnet, typically Nd2 Fe14 B system) having a sufficient thickness in a magnetization direction, effecting diffusion reaction of Dy or Tb inward from the surfaces of the magnet block excluding the surfaces perpendicular to the magnetization direction, thereby producing the magnet block in which the coercive force near the surfaces is higher than in the interior, and cutting the magnet block in a direction perpendicular to the magnetization direction by means of a cutter blade, wire saw or the like, a plurality of magnet segments of predetermined size can be manufactured from one magnet block absorption” [0025] and as a result, throughput of the process is improved.
It would have been obvious to one of ordinary skill in the art before the effective filing date to have applied the diffusion treatment using heavy rare earth magnets as taught by Miyata to the sintered magnet of Hidaka to achieve predictable results. Miyata and Hidaka are both directed to diffusion treatment of heavy rare earth elements into NdFeB sintered magnets (i.e. same field of endeavor). Furthermore, Miyata states that performing the diffusion treatment in this manner allows for the production of multiple magnet segments from one magnet block diffusion which increases the throughput of the process. As such, an ordinarily skilled artisan would be motivated to combine the teachings of Miyata and Hidaka and would have a reasonable expectation of success.
Hidaka discloses that Tb (interpreted as the heavy rare earth) can be used in the form of an alloy [0100]. Likewise, Miyata teaches that the Dy or Tb diffusion source can be in the form of an alloy containing Dy or Tb [0044, Claim 1]. However, Hidaka in view of Miyata does not explicitly teach the composition of said alloy.
Sun teaches producing a sintered NdFeB magnet [Title] wherein an infiltration step is performed on a base magnetic material to form a grain boundary phase [Page 3, “Summary of Invention”]. Sun teaches that the grain boundary infiltration is an alloy of Ra-Al-X, wherein Ra can be Dy or Tb, and X can include Cu and Ga (as well as optionally Co or Zr) [Page 3, “Summary of Invention”]. Sun teaches that Al reduces the melting point, increases fluidity and wettability; Cu helps increase the coercive force of the magnet, and Ga improves lubricity of the grain boundary and suppresses grain growth [Page 3, “Summary of Invention”]. Lastly, as shown in Tables 1, 3, 5, 7 and 9, the rare earth component of the alloy can range from 40 – 90 wt% (implying the total of the other elements is 10 – 60 wt%), which overlap with the claimed range of HR and “M”. Sun also teaches that the rare earth alloy improves coercivity and corrosion resistance [Page 3, 2nd and 3rd paragraph].
It would have been obvious to one of ordinary skill in the art before the effective filing date to have used the heavy rare earth alloy of Sun in Hidaka as-modified by Miyata. Hidaka, Miyata, and Sun are directed to grain boundary formation of heavy rare earth elements into NdFeB sintered magnets (i.e. same field of endeavor). Furthermore, Hidaka and Miyata both explicitly acknowledge that the heavy rare earth component for diffusion can be an alloy containing said element [0100, Hidaka and 0044, Miyata] and therefore, an ordinarily skilled artisan would have a reasonable expectation of success. As well, a person of ordinary skill in the art would be motivated to use the heavy rare earth alloy taught by Sun because the alloy includes Al and can further include Cu and Ga which each provide different benefits to the infiltration process and/or the magnet itself. These include reducing the melting point, increasing fluidity and wettability for Al; increasing the coercive force of the magnet for Cu, and improving lubricity of the grain boundary and suppressing grain growth for Ga [Page 3, “Summary of Invention”]. Additionally, Sun teaches that the rare earth alloy improves coercivity and corrosion resistance [Page 3, 2nd and 3rd paragraph], both properties would be appreciated by Hidaka which explicitly measures these properties [Table 2]
With regards to the overlapping ranges taught, it would have been obvious to an ordinarily skilled artisan before the effective filing date of the claimed invention to have selected overlapping ranges as disclosed. Selection of overlapping ranges has been held to be a prima facie case of obviousness (See MPEP § 2144.05 I). “In the case where the claimed ranges "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)”.
"[W]here 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. "The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages.". (See MPEP § 2144.05 II)
Regarding claims 2 – 3, Hidaka in view of Miyata and Sun teaches the invention as applied to claim 1. Given that “any two points spaced from the diffusion plane by a distance of no more than 500 µm” can include two points essentially next to each (i.e. a distance of ~0 µm), two points this close would possess a ratio of HR content that was approximately identical (i.e. ~1.0), meeting the claimed range. Additionally, Hidaka teaches that the concentration ratio of Tb at the surface to core is 0.4 – 1.0 [0065].
Regarding claim 4, Hidaka in view of Miyata and Sun teaches the invention as applied to claim 1. The exemplary alloy of Hidaka teaches containing 0.15 mass% Zr and 0.04 mass% Mn, wherein both of these elements are within the list of “T” elements (meeting the claimed “at least one of the following”) and are a total of 0.19 mass%, which falls within the claimed range of “T” elements [Table 1, Example 2].
Regarding claim 5, Hidaka in view of Miyata and Sun teaches the invention as applied to claim 1. The exemplary alloy of Hidaka teaches containing 0.2 mass% Al, 0.2 mass% Ga, and 0.2 mass% Cu, wherein the total is 0.6 mass%, which falls within the claimed total range of the elements [Table 1, Example 2]
Regarding claims 8 and 11 – 15, Hidaka in view of Miyata and Sun teaches the invention as applied to claims 1 – 5, respectively. Miyata shows that the sintered magnet is formed into a square block for the diffusion treatment, meeting the claimed limitation of claim 8 and 11 – 15 [Fig 1A].
Response to Arguments
Applicant's arguments filed 12/29/2025 have been fully considered but they are not persuasive.
In regards to the introduced limitations in claim 1. The examiner notes that the claims are directed to a product and a product is not limited by the manipulation of the recited steps, only the structure implied (MPEP 2113 I). Hidaka discloses using a sintered magnet in the diffusion treatment, which meets the claimed structure. For purposes of compact prosecution the examiner notes that Hidaka discloses the sintered magnet is produced by strip casting the magnet alloy composition, introduction hydrogen into the alloy and pulverizing, then molding the alloy powder in a magnetic field [0120, 0121, 0125], meeting the claimed steps.
Moreover, applicant argues that Sun teaches performing the infiltration/diffusion process prior to sintering which is at a different stage/step than the claimed invention. Applicant argues that thus, there is no magnetization direction and therefore, an ordinarily skilled artisan would not have been led to the diffusion direction relative to magnetization direction. This not found persuasive. Sun is not relied upon for the teaching of the diffusion step.
Hidaka is directed to diffusion of a heavy rare earth alloy into a sintered NdFeB body and Miyata explicitly states “that by providing a sintered Nd base magnet block (sintered rare earth magnet, typically Nd2 Fe14 B system) having a sufficient thickness in a magnetization direction, effecting diffusion reaction of Dy or Tb inward from the surfaces of the magnet block excluding the surfaces perpendicular to the magnetization direction, thereby producing the magnet block in which the coercive force near the surfaces is higher than in the interior, and cutting the magnet block in a direction perpendicular to the magnetization direction by means of a cutter blade, wire saw or the like, a plurality of magnet segments of predetermined size can be manufactured from one magnet block absorption” [0025] and as a result throughput of the process is improved. Thus, the prior art teaches the diffusion step into a sintered body and an express benefit as to why an ordinarily skilled artisan would have performed the diffusion treatment in the direction(s) relative to the magnetization direction that is claimed. Applicant’s argument against the individual prior art of Sun (which is relied upon for a diffusion alloy composition) is not persuasive because the rejection is view of the combination of Hidaka, Miyata, and Sun and 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).
Applicant further argues that because Sun performs diffusion at a different step/stage, the benefits described would not be applicable to the method of Hidaka. This is not found persuasive. Sun states that the alloy includes Al and can further include Cu and Ga which each provide different benefits to the infiltration process and/or the magnet itself.
For Al, this includes reducing the melting point as well as increasing fluidity and wettability. These benefits of reducing the melting point, increasing fluidity, and increasing wettability would also be applicable to bulk body because they would promote diffusion of the component.
Sun states that Cu increases the coercive force of the magnet which would also be applicable to a bulk body and would be a benefit appreciated in the disclosure of Hidaka because it’s directed to improve magnetic properties. Copper also has a lower melting point than Tb or Dy which would naturally improve fluidity of their diffusion as well.
Sun states that Ga improves lubricity of the grain boundary and suppresses grain growth [Page 3, “Summary of Invention”]. These would also be benefits applicable in a bulk body diffusion treatment. Additionally, gallium would also serve to reduce the melting point of the alloy given gallium’s low melting point which would naturally improve fluidity of the diffusion as well.
Lastly, applicant has not provided any evidence as to why these benefits would not be applicable to the prior art of Hidaka and as such, the arguments are not found persuasive.
Conclusion
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 Austin M Pollock whose telephone number is (571)272-5602. The examiner can normally be reached M - F (11 - 8 ET).
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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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/AUSTIN POLLOCK/Examiner, Art Unit 1738
/SALLY A MERKLING/SPE, Art Unit 1738
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