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 .
Response to Amendments, Election/Restrictions and Status of Claims
Applicant’s amendments to the claims, filed March 11, 2026, are acknowledged. Claims 14-20 are amended. No new matter has been added.
Applicant’s election of Invention I, Claims 1-13, drawn to a method for treating magnetic material, in the reply filed on March 11, 2026, is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)).
Claims 14-20, previously drawn to nonelected inventions directed to a permanent magnet and to an electric motor, have been amended (see above) to be directed to the method of Claim 1, and therefore Claims 1-20 are currently pending and considered in this office action.
Claim Interpretation
It is interpreted that hard magnetic alloy in molten form reads on providing hard magnetic particles (Claim 1) and on providing hard magnetic particles in liquid form (Claim 13) (para. [0052] of instant specification hard magnetic materials may also be provided in liquid form (e.g., molten Mn-Bi)).
Claim Rejections - 35 USC § 102
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 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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 11-12, 14 and 17 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Ishii (US 20170098497 A1).
Regarding Claim 1, Ishii discloses a method for treating magnetic material (Abstract; para. [0001]; para. [0004]), the method comprising:
providing hard magnetic particles (para. [0045]);
increasing the magnetic coercivity of the hard magnetic particles by polishing the hard magnetic particles (para. [0004], pulverization step reads on polishing; see Fig. 1 and para. [0023], wherein pulverization smooths powder surfaces; para. [0041]-[0042]; see para. [0127], wherein pulverization and obtaining the particular L/d ratio therefrom improves coercivity); and
forming a permanent magnet, the permanent magnet comprising the polished hard magnetic particles (para. [0004]).
Additionally, the polishing step is the same as claimed, and it would be appreciated that the magnetic coercivity of the hard magnetic particles would increase by polishing as claimed because the hard magnetic particles and polishing step are the same as claimed. When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Regarding Claim 11, Ishii discloses wherein forming the permanent magnet further comprises densifying the polished hard magnetic material by sintering the polished hard magnetic material at a temperature above 300°C (para. [0084], 950-1100C; para. [0078] and para. [0086]).
Regarding Claim 12, Ishii discloses increasing a magnetic anisotropy of the hard magnetic particles by polishing the hard magnetic particles (para. [0127], wherein pulverization and obtaining the particular L/d ratio therefrom improves alignment degree, which reads on magnetic anisotropy).
Additionally, the polishing step is the same as claimed, and it would be appreciated that the magnetic anisotropy of the hard magnetic particles would increase by polishing as claimed because the hard magnetic particles and polishing step are the same as claimed. When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Regarding Claim 14, Ishii discloses wherein the permanent magnet comprises the polished hard magnetic particles, wherein a plurality of the polished hard magnetic particles comprise a rounded surface along a perimeter of a cross-section of the polished hard magnetic particles (Fig. 1(a), polished surface is rounded; para. [0100]; para. [0004]-[0005], wherein polished (pulverized) powder is used to manufacture permanent magnet).
Regarding Claim 17, Ishii discloses wherein the polished hard magnetic particles comprise densified polished hard magnetic particles (para. [0078] and para. [0086], densifying of powders).
Claims 1-2, 9-10 and 12-17 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Katayama (US 20190027283 A1).
Regarding Claim 1, Katayama discloses a method for treating magnetic material (Abstract), the method comprising:
providing hard magnetic particles (para. [0049], raw materials provided in powder form; see also para. [0045], providing pulverized and sintered material reads on providing hard magnetic particles; para. [0052], coarse pulverization; see para. [0046], melted and atomized which reads on providing liquid hard magnetic particles – see instant specification para. [0015]);
polishing the hard magnetic particles (para. [0049], wherein pulverized and sintered particles are further pulverized, second pulverization step reads on polishing; see also para. [0052], fine pulverization after coarse pulverization; para. [0046], solidification of liquid hard magnetic particles reads on polishing – see instant specification para. [0059]); and
forming a permanent magnet, the permanent magnet comprising the polished hard magnetic particles (Abstract).
Katayama fails to disclose wherein polishing increases the coercivity of the hard magnetic particles; however, the polishing steps (second pulverization of the pulverized and sintered particles – see para. [0045] and para. [0052], and solidification of the atomized liquid hard metal particles – see para. [0046]) are the same as the instant invention (see para. [0058]; see para. [0059], atomizing of molten metal), and it would be appreciated that the magnetic coercivity of the hard magnetic particles would increase by polishing as claimed because the particle types and polishing steps (hard magnetic particles which are pulverized or liquid hard magnetic particles which are solidified by atomization) are the same as claimed.
When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Regarding Claim 2, Katayama discloses providing manganese bismuth (Mn-Bi) alloy particles in powder form (para. [0045]; see also para. [0049], Mn-Bi provided in powder form).
Regarding Claim 9, Katayama discloses bonding the polished hard magnetic material to a polymer matrix while magnetically orienting the hard magnetic material (Abstract; para. [0056]; para. [0061]).
Regarding Claim 10, Katayama discloses molding the polished hard magnetic material coupled to a polymer matrix via compression molding, transfer molding, or injection molding (Abstract; para. [0056]; para. [0061]).
Regarding Claim 12, Katayama fails to disclose wherein polishing increases the magnetic anisotropy of the hard magnetic particles; however, the polishing steps (second pulverization of the pulverized and sintered particles – see para. [0045] and para. [0052]), and solidification of the atomized liquid hard metal particles – see para. [0046]) are the same as the instant invention (see para. [0058]; see para. [0059], atomizing of molten metal), and it would be appreciated that the magnetic anisotropy of the hard magnetic particles would increase by polishing as claimed because the particle types and polishing steps (hard magnetic particles which are pulverized or liquid hard magnetic particles which are solidified by atomization) are the same as claimed. When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Regarding Claim 13, Katayama discloses providing the hard magnetic particles in liquid form, and wherein polishing the hard magnetic particles further comprises atomizing the liquid hard magnetic particles by exposing a stream of the liquid hard magnetic particles to an atomization force (para. [0046]; see instant specification para. [0015] and para. [0059]). One of ordinary skill in the art would appreciate that melting and atomizing to form an alloy powder involves atomizing a stream of liquid particles by exposure to an atomization force, as claimed.
Regarding Claim 14, Katayama discloses melting and atomizing to form hard magnetic powder, and one ordinary skill in the art would appreciate atomized powder would comprised a near spherical shape and therefore rounded surface along a perimeter of a cross-section of the particle, as claimed (para. [0046]; see also para. [0059] of instant specification).
Further, the polishing step, the polishing steps (second pulverization of the pulverized and sintered particles – see para. [0045] and para. [0052], and solidification of the atomized liquid hard metal particles – see para. [0046]) are the same as the instant invention (see para. [0058]; see para. [0059], atomizing of molten metal), and it would be appreciated that the magnetic anisotropy of the hard magnetic particles would increase by polishing as claimed because the particle types and polishing steps (hard magnetic particles which are pulverized or liquid hard magnetic particles which are solidified by atomization) are the same as claimed. When the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP 2112.01.
Regarding Claim 15, Katayama discloses wherein the permanent magnet comprises a polymer matrix bonded to the polished hard magnetic particles (Abstract; para. [0061]-[0062]).
Regarding Claim 16, Katayama discloses wherein the polished hard magnetic particles comprise Mn-Bi alloy particles (Abstract and [0044]-[0049]).
Regarding Claim 17, Katayama discloses wherein the polished hard magnetic particles comprise densified polished hard magnetic particles (para. [0056] and para. [0061]-[0062], hot compression and pressure molding reads on densifying).
Claim Rejections - 35 USC § 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 3-6 are rejected under 35 U.S.C. 103 as being unpatentable over Ishii (US 20170098497 A1), as applied to Claim 1 above, in view of Sagawa (US 20070245851 A1).
Regarding Claim 3, Ishii discloses wherein coarse pulverization comprises mechanical pulverization, which also reads on mechanically polishing, and one of ordinary skill in the art would appreciate this process to occur in a container (para. [0047]-[0052], coarse pulverization reads on both providing a hard magnetic particle and polishing).
Ishii discloses wherein fine pulverization includes a pulverization chamber and is considered friction grinding (para. [0052]). One of ordinary skill in the art would appreciate friction grinding, and the grinding from particle to particle contact and particle contact with the pulverization chamber, reads on mechanical polishing because polishing is occurring from mechanical impact.
Further, Sagawa teaches wherein fine pulverization may use a ball mill, an attritor, or jet mill pulverization, and either method is suitable to produce a fine powder having a grain size of a few micrometers (para. [0194]). Thus, Sagawa teaches the art equivalence of ball milling to jet mill pulverization for fine pulverization techniques.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used ball milling for the fine pulverization and therefore mechanical polishing in a container as claimed, as taught by Sagawa, for the invention disclosed by Ishii, in order to produce a fine powder having a grain size of a few micrometers and because Sagawa demonstrates the art equivalence of ball milling to jet mill pulverization (see teachings above and MPEP 2144.06.II).
Ishii teaches wherein hard magnetic particles are susceptible to oxygen after the coarse grinding and therefore handled in an inert gas after pulverization (para. [0050]).
Further, Sagawa teaches wherein process steps after the preparation of the fine powder (after milling) and until sintering are performed under an inert atmosphere, thereby enabling the use of smaller powder sizes and reducing oxygen impurities which deteriorate magnetic properties (para. [0165]; para. [0193]; para. [0203]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used an inert atmosphere for the removal of the fine powder from the milling container and until sintering, which reads on the claimed controlled atmosphere condition during particle removal, as taught by Sagawa, for the invention disclosed by Ishii, in order to enable smaller powder sizes and to reduce oxygen impurities which deteriorate magnetic properties (see teachings above).
Regarding Claim 4, one of ordinary skill in the art would appreciate that mechanical polishing by ball milling (see teaching by Sagawa) comprises frictional force between particles and between particles and the container wall, which reads on the claimed frictional force between at least two hard magnetic particles of the hard magnetic particles.
Regarding Claim 5, one of ordinary skill in the art would appreciate that mechanical polishing by ball milling (see teaching by Sagawa) comprises frictional force between particles and between particles and the container wall, which reads on the claimed frictional force exerted by a surface of the polishing container onto the hard magnetic particles.
Regarding Claim 6, the ball media for the mechanical polishing by ball milling (see teaching by Sagawa) reads on providing free polishing structures within the polishing container.
Claims 7-8 are rejected under 35 U.S.C. 103 as being unpatentable over Ishii (US 20170098497 A1) in view of Sagawa (US 20070245851 A1), as applied to Claim 3 above, in further view of Ebe (US 20190221339 A).
Regarding Claim 7, Ishii discloses wherein fine pulverization parameters are selected based on achieving a particle size of 1-5.5um (para. [0056]-[0061]).
Sagawa further discloses using ball milling to achieve a particular powder size (para. [0115], 4um or less; para. [0193], d50 of 1-3um), but fails to disclose an operating speed of the polishing container.
Ebe teaches coarse Nd-Fe-B type powder which is further pulverized by ball milling with a rotational speed of 500 rpm in order to achieve a particle size of 1um (para [0066]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified ball milling parameters to achieve a desired particle size, such as a rotational speed of 500rpm, as taught by Ebe, for the invention of Ishii and Sagawa. One would be motivated to do this in order to achieve a particle size of rare earth hard magnetic powder of 1um, as desired by Ishii and Sagawa. Therefore, Ishii, Sagawa and Ebe disclose the claimed limitation of operating a speed of the polishing container based on a particle size (1um) and/or hardness (Nd-Fe-B type composition) of the hard magnetic material.
Regarding Claim 8, Ishii discloses wherein fine pulverization parameters are selected based on achieving a particle size of 1-5.5um (para. [0056]-[0061]).
Sagawa further discloses using ball milling to achieve a particular powder size (para. [0115], 4um or less; para. [0193], d50 of 1-3um), but fails to disclose operating parameters of the polishing container.
Ebe teaches coarse Nd-Fe-B type powder which is further pulverized by ball milling using a container volume of 0.8L with a rotational speed of 500 rpm in order to achieve a particle size of 1um (para [0066]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified ball milling parameters to achieve a desired particle size, such as modifying a container volume and rotational speed (for example, 0.8L and 500rpm), as taught by Ebe, for the invention of Ishii and Sagawa. One would be motivated to do this in order to achieve a particle size of rare earth hard magnetic powder of 1um, as desired by Ishii and Sagawa. Therefore, Ishii, Sagawa and Ebe comprise the claimed limitation of operating a speed of the polishing container based on a spatial dimension of a portion of the container that the hard magnetic particles interact with.
Claims 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Katayama (US 20190027283 A1), as applied to Claim 1, in further view of Rong (US 20220077725 A1).
Regarding Claim 18, Katayama discloses wherein Mn-Bi magnet powder is utilized as a magnet for motors due to high saturation magnetization and large magnetocrystalline anisotropy (para. [0002]), but is silent towards the details of motor type, and does not disclose usage and therefore assembly in an electric motor comprising a rotor and stator.
Rong teaches where a MnBi permanent magnet may be used for an electric motor comprising a rotor and stator because these materials have a high coercivity to provide anti-demagnetizing ability during motor operation (Abstract; para. [0015]-[0016]; para. [0027]; para. [0035]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used and therefore assembled the MnBi permanent magnet of Katayama into an electric motor comprising a rotor and stator, as taught by Rong, because MnBi is a suitable material for the electric motor due to having high saturation magnetization and large magnetocrystalline anisotropy, and further due to having a high coercivity which provides anti-demagnetizing ability during motor operation (see teachings above by Katayama and Rong). Additionally, it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 125 USPQ 416. See MPEP 2144.07.
Regarding Claim 19, Katayama discloses wherein the permanent magnet further comprises a polymer matrix bonded to the polished hard magnetic particles (Abstract; para. [0061]).
Regarding Claim 20, Katayama discloses wherein the polished hard magnetic particles comprise Mn-Bi alloy particles (Abstract and [0044]-[0049]).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Nagata (US 20150279530 A1): discloses a method for treating magnetic material comprising strip casting molten rare earth magnet material to form a quenched alloy, crushing and milling the quenched alloy using a hybrid process of ball milling and hydrogen decrepitation to form a treated powder, and forming a permanent magnet with the treated powder (Abstract; providing hard magnetic particles (para. [0010]; para. [0039]; para. [0043]).
One of ordinary skill in the art would appreciate that crushing and milling would both provide a hard magnetic particles by crushing the quenched alloy and further polish the hard magnetic particles of the crushed quenched alloy by the prolonged and continued ball milling (see also para. [0068], ball milling introduces further process of milling which reads on polishing).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CATHERINE P SMITH whose telephone number is (303)297-4428. The examiner can normally be reached Monday - Friday 9:00-4:00 MT.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Walker can be reached at (571)-272-3458. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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CATHERINE P. SMITH
Patent Examiner
Art Unit 1735
/CATHERINE P SMITH/Examiner, Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735
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