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 Amendment and Status of Claims
Applicant’s amendments to the claims, filed July 1, 2026, are acknowledged. Claims 1, 3, 16 and 18 are amended.
Claims 1-20 are currently pending and considered in this office action.
Claim Interpretation
The hard magnetic alloy in molten form is interpreted to read on providing hard magnetic particles (Claim 1) and 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)).
Regarding Claim 11, it is interpreted that densification by heating within the claimed range of above 300C meets the claimed limitations and reads on sintering.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claim 13 rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
While there is support for the combination of polishing techniques of mechanical polishing and chemical polishing (para. [0056]), there does not appear to be language or support in the disclosure describing both polishing by atomization of liquid particles and further, by mechanical polishing (see para. [0056]-[0058], wherein atomization appears to be a separate and mutually exclusive polishing method to the mechanical polishing).
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.
Claim 11 is 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.
Regarding Claim 11, the claims require that the final permanent magnet comprises a binder (see Claim 1 from which Claim 11 depends), while Claim 11 requires sintering above 300C. It is unclear how the sintered material comprises the binder (see para. [0061], wherein permanent magnet may be bonded and comprise a binder, or may be sintered (i.e., no binder)).
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.
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 1-2, 9-10 and 12-17 are rejected under 35 U.S.C. 103 as being unpatentable over Katayama (previously cited, US 20190027283 A1) in view of Kim (US 20160035487 A1) and Sagawa (previously cited, US 20070245851 A1).
Regarding Claim 1, Katayama discloses a method for treating magnetic material (Abstract), the method comprising:
providing hard magnetic particles comprising primarily MnBi alloy particles (para. [0018], [0045]-[0049]; 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 pulverization after sintering reads on polishing; para. [0052], fine pulverization after coarse pulverization; para. [0060]; 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 primarily the polished hard magnetic particles and a binder (Abstract).
Katayama discloses applying fine pulverization to achieve a powder with a single domain size (para. [0052]), but is silent towards pulverization techniques.
Kim teaches pulverizing Mn-Bi-based material by ball milling in order to achieve powder with a single domain size (para. [0049]). One of ordinary skill in the art would appreciate that ball milling is mechanical polishing which would occur in a container that is rotated, as claimed.
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, and therefore mechanical polishing in a container that is rotated, as taught by Kim, for the pulverization steps of Katayama, in order to achieve MnBi powder with a single domain size, as required by Katayama (see teachings by Kim above).
Kim further teaches avoiding the oxidation of Mn in order to maintain magnetic properties (para. [0048]; para. [0077]).
Further, Katayama teaches suppressing oxidation in order to obtain sufficiently high magnetic properties, including performing steps such as compression molding in an inert atmosphere (para. [0015]; para. [0056]).
Kim and Katayama, however, do not expressly disclose removal of the hard magnetic particles from the polishing container (ball milling container) with simultaneous exposure to an environment without oxygen and/or moisture.
Sagawa teaches wherein steps of ball milling to achieve a fine powder and subsequent steps up to and including consolidation are performed in an inert atmosphere or vacuum, thereby enabling the use of smaller powder sizes and reducing oxygen impurities which deteriorate magnetic properties (para. [0165]; para. [0193]; para. [0203]). While Sagawa is directed to rare-earth powders, Katayama and Kim similarly recognize that oxidation deteriorates MnBi powder, and one ordinary skill in the art would readily apply the teachings of Sagawa for the same purpose of oxidation suppression and to avoid deterioration of magnetic properties.
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 or vacuum for the removal of the fine powder from the ball milling container and until consolidation, which reads on the claimed controlled environment condition, as taught by Sagawa, for the invention disclosed by Katayama and Kim, in order to enable smaller powder sizes and to reduce oxygen impurities which deteriorate magnetic properties (see teachings above).
Katayama fails to disclose wherein the mechanical polishing increases the coercivity of the hard magnetic particles; however, the provided hard MnBi magnetic particles of Katayama are the same as claimed, and the mechanical polishing steps ( ball milling) of Kim are the same as claimed (see above teachings). Therefore, one of ordinary skill in the art would appreciate that the magnetic coercivity of the hard magnetic particles would increase the same as claimed because the starting material and processing steps are the same.
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). See claim interpretation above.
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 11, Katayama discloses densifying the polished hard magnetic material by sintering the polished hard magnetic material at a temperature above 300C (para. [0056], 280-380C reads on above 300C).
Regarding Claim 12, Katayama fails to disclose wherein polishing increases the magnetic anisotropy of the hard magnetic particles; however, the provided hard MnBi magnetic particles of Katayama are the same as claimed, and the mechanical polishing steps ( ball milling) of Kim are the same as claimed (see above teachings). Therefore, one of ordinary skill in the art would appreciate that the magnetic anisotropy of the hard magnetic particles would increase the same as claimed because the starting material and processing steps are the same.
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 comprise 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 provided hard MnBi magnetic particles of Katayama are the same as claimed, and the mechanical polishing steps ( ball milling) of Kim are the same as claimed (see above teachings). Therefore, one of ordinary skill in the art would appreciate that the polished hard magnetic particles would comprise a rounded surface along a perimeter of a cross-section, 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).
Claims 3-6 are rejected under 35 U.S.C. 103 as being unpatentable over Katayama (previously cited, US 20190027283 A1) in view of Kim (US 20160035487 A1) and Sagawa (previously cited, US 20070245851 A1), as applied to Claim 1 above, in further view of Nagata (previously cited, US 20150279530 A1).
Regarding Claim 3, Kim does not expressly disclose wherein the polishing container contains an abrasive lining.
However, Nagata explains wherein ball milling produces frictional forces from both the rigid balls and the inner wall of the container, and milling work occurs from impact with the inner wall of the container, which is the same as the instant invention (Nagata, para. [0044]; instant specification, para. [0058], “abrasive lining…in other words…mechanically polished by using a frictional force exerted by a surface of the polishing container”).
Thus, one of ordinary skill in the art would appreciate that the ball milling container of Kim would comprise an abrasive lining because the inner wall of the ball milling container of Kim would produce frictional forces upon the material being ball milled, as taught by Nagata.
Regarding Claim 4, one of ordinary skill in the art would appreciate that mechanical polishing by ball milling (see teaching by Kim) 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 (see teaching above by Nagata).
Regarding Claim 5, one of ordinary skill in the art would appreciate that mechanical polishing by ball milling (see teaching by Kim) 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 (see teaching above by Nagata).
Regarding Claim 6, the ball media for the mechanical polishing by ball milling (see teaching by Kim) 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 Katayama (previously cited, US 20190027283 A1) in view of Kim (US 20160035487 A1) and Sagawa (previously cited, US 20070245851 A1) and Nagata (previously cited, US 20150279530 A1), as applied to Claim 3 above, in further view of Lu (CN 117133522 A, English Machine Translation provided).
Regarding Claim 7, Kim teaches applying a particular ball milling time in order to achieve the desired single domain powder size, but is silent towards an operating speed based on the particle size.
Lu teaches achieving a 1.5-15um MnBi powder size by ball milling from 4-10hours at 150-200rpm (para. [0015]; para. [0008], which falls within the milling times disclosed by Kim of 2-5 hours and the single domain particle sizes disclosed by Kim and Katayama (Kim, para. [0047] and para. [0049]; Katayama, para. [0065]).
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 a ball milling operating speed based on a particular particle size, as taught by Lu, for the invention disclosed by Katayama and Kim, in order to powder with a powder size which is a single magnetic domain size (see teachings above).
Regarding Claim 8, Kim teaches applying a particular ball milling time in order to achieve the desired single domain powder size, but is silent towards an operating speed based on a spatial dimension of a portion of the container.
Lu teaches achieving a 1.5-15um MnBi powder size by ball milling from 4-10hours at 150-200rpm in a 1L planetary ball mill (para. [0015]; para. [0008]; para. [0028]), which falls within the milling times disclosed by Kim of 2-5 hours and the single domain particle sizes disclosed by Kim and Katayama (Kim, para. [0047] and para. [0049]; Katayama, para. [0065]).
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 a ball milling operating speed based on a spatial dimension (1L) of the polishing container, as taught by Lu, for the invention disclosed by Katayama and Kim, in order to powder with a powder size which is a single magnetic domain size (see teachings above).
Claims 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Katayama (previously cited, US 20190027283 A1) in view of Kim (US 20160035487 A1) and Sagawa (previously cited, US 20070245851 A1), as applied to Claim 1 above, in further view of Rong (previously cited, 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]).
Response to Arguments
Applicant’s arguments, filed July 1, 2026, with respect to Claims 1, 11-12, 14 and 17 rejected under 35 U.S.C. 102(a)(1) over Ishii, and Claims 1-2, 9-10 and 12-17 rejected under 35 U.S.C. 102(a)(1) over Katayama, have been fully considered and are persuasive in view of Applicant’s amendments to the claims further limiting the polishing step and permanent magnet composition. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view over Katayama in view of Kim and Sagawa, as detailed above.
Applicant’s arguments are deemed moot in view of the new grounds of rejection.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Nagata (previously cited and applied above, US 20150279530 A1, further teachings): 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 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).
Ishii (previously cited, US 20170098497 A1): teaches a method comprising forming polished hard magnetic MnBi particles hydrogen desorption and friction grinding such as jet milling (Abstract; para. [0001]; para. [0004]; para. [0047]-[0052], coarse pulverization reads on both providing a hard magnetic particle and polishing).
Ishii further teaches increasing the magnetic coercivity and increasing a magnetic anisotropy of the hard magnetic particles by polishing the hard magnetic particles (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 improves alignment degree, which reads on magnetic anisotropy).
Ishii also teaches densifying the polished hard magnetic material by sintering the polished hard magnetic material at 950-1100C (para. [0084]; para. [0078] and para. [0086]).
Sagawa (previously cited and applied above, US 20070245851 A1, further teachings): 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.
Ebe (previously cited, US 20190221339 A): 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]).
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to 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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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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